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ウェブページのメタデータ</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs">HTML の見出しと段落</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance">強調と重要性</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Lists">リスト</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Structuring_documents">文書とウェブサイトの構造</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features">高度なテキスト装飾</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Creating_links">リンクの作成</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter">課題: 手紙のマークアップ</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content">課題: コンテンツのページの構造化</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/HTML_images">HTML の画像</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio">動画と音声のコンテンツ</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Mozilla_splash_page">Mozilla のスプラッシュページ</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics">HTML の表の基本</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Table_accessibility">HTML 表のアクセシビリティ</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Planet_data_table">課題: 惑星データの構造化</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/HTML_forms">HTML におけるフォームとボタン</a></li><li><a href="/ja/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML">HTML のデバッグ</a></li></ol></details></li></ol></details></li><li class="toggle"><details><summary>ガイド</summary><ol><li><a href="/ja/docs/Web/HTML/Content_categories">コンテンツカテゴリー</a></li><li><a href="/ja/docs/Glossary/Block-level_content">ブロックレベル要素</a></li><li><a href="/ja/docs/Glossary/Inline-level_content">インライン要素</a></li><li><a href="/ja/docs/Web/HTML/Quirks_Mode_and_Standards_Mode">互換モードと標準モード</a></li><li><a href="/ja/docs/Web/HTML/Date_and_time_formats">HTML で使用される日付と時刻の形式</a></li><li><a href="/ja/docs/Web/HTML/Constraint_validation">制約検証</a></li><li><a href="/ja/docs/Web/HTML/Microdata">Microdata</a></li><li><a href="/ja/docs/Web/HTML/microformats">Microformats</a></li><li><a href="/ja/docs/Web/HTML/Viewport_meta_tag">ビューポートメタタグ</a></li><li><a href="/ja/docs/Web/HTML/CORS_enabled_image">別オリジンの画像とキャンバスを利用可能にする</a></li></ol></details></li><li class="section"><a href="/ja/docs/Web/HTML/Reference">リファレンス</a></li><li class="toggle"><details open=""><summary>HTML 要素</summary><ol><li><a href="/ja/docs/Web/HTML/Element/a"><code><a></code></a></li><li><a href="/ja/docs/Web/HTML/Element/abbr"><code><abbr></code></a></li><li><a href="/ja/docs/Web/HTML/Element/acronym"><code><acronym></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/address"><code><address></code></a></li><li><a href="/ja/docs/Web/HTML/Element/area"><code><area></code></a></li><li><a href="/ja/docs/Web/HTML/Element/article"><code><article></code></a></li><li><a href="/ja/docs/Web/HTML/Element/aside"><code><aside></code></a></li><li><a href="/ja/docs/Web/HTML/Element/audio"><code><audio></code></a></li><li><a href="/ja/docs/Web/HTML/Element/b"><code><b></code></a></li><li><a href="/ja/docs/Web/HTML/Element/base"><code><base></code></a></li><li><a href="/ja/docs/Web/HTML/Element/bdi"><code><bdi></code></a></li><li><a href="/ja/docs/Web/HTML/Element/bdo"><code><bdo></code></a></li><li><a href="/ja/docs/Web/HTML/Element/big"><code><big></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/blockquote"><code><blockquote></code></a></li><li><a href="/ja/docs/Web/HTML/Element/body"><code><body></code></a></li><li><a href="/ja/docs/Web/HTML/Element/br"><code><br></code></a></li><li><a href="/ja/docs/Web/HTML/Element/button"><code><button></code></a></li><li><a href="/ja/docs/Web/HTML/Element/canvas"><code><canvas></code></a></li><li><a href="/ja/docs/Web/HTML/Element/caption"><code><caption></code></a></li><li><a href="/ja/docs/Web/HTML/Element/center"><code><center></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/cite"><code><cite></code></a></li><li><a href="/ja/docs/Web/HTML/Element/code"><code><code></code></a></li><li><a href="/ja/docs/Web/HTML/Element/col"><code><col></code></a></li><li><a href="/ja/docs/Web/HTML/Element/colgroup"><code><colgroup></code></a></li><li><a href="/ja/docs/Web/HTML/Element/data"><code><data></code></a></li><li><a href="/ja/docs/Web/HTML/Element/datalist"><code><datalist></code></a></li><li><a href="/ja/docs/Web/HTML/Element/dd"><code><dd></code></a></li><li><a href="/ja/docs/Web/HTML/Element/del"><code><del></code></a></li><li><a href="/ja/docs/Web/HTML/Element/details"><code><details></code></a></li><li><em><a href="/ja/docs/Web/HTML/Element/dfn" aria-current="page"><code><dfn></code></a></em></li><li><a href="/ja/docs/Web/HTML/Element/dialog"><code><dialog></code></a></li><li><a href="/ja/docs/Web/HTML/Element/dir"><code><dir></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/div"><code><div></code></a></li><li><a href="/ja/docs/Web/HTML/Element/dl"><code><dl></code></a></li><li><a href="/ja/docs/Web/HTML/Element/dt"><code><dt></code></a></li><li><a href="/ja/docs/Web/HTML/Element/em"><code><em></code></a></li><li><a href="/ja/docs/Web/HTML/Element/embed"><code><embed></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/fencedframe" class="only-in-en-us"><code><fencedframe></code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/fieldset"><code><fieldset></code></a></li><li><a href="/ja/docs/Web/HTML/Element/figcaption"><code><figcaption></code></a></li><li><a href="/ja/docs/Web/HTML/Element/figure"><code><figure></code></a></li><li><a href="/ja/docs/Web/HTML/Element/font"><code><font></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/footer"><code><footer></code></a></li><li><a href="/ja/docs/Web/HTML/Element/form"><code><form></code></a></li><li><a href="/ja/docs/Web/HTML/Element/frame"><code><frame></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/frameset"><code><frameset></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/Heading_Elements"><code><h1></code></a></li><li><a href="/ja/docs/Web/HTML/Element/head"><code><head></code></a></li><li><a href="/ja/docs/Web/HTML/Element/header"><code><header></code></a></li><li><a href="/ja/docs/Web/HTML/Element/hgroup"><code><hgroup></code></a></li><li><a href="/ja/docs/Web/HTML/Element/hr"><code><hr></code></a></li><li><a href="/ja/docs/Web/HTML/Element/html"><code><html></code></a></li><li><a href="/ja/docs/Web/HTML/Element/i"><code><i></code></a></li><li><a href="/ja/docs/Web/HTML/Element/iframe"><code><iframe></code></a></li><li><a href="/ja/docs/Web/HTML/Element/img"><code><img></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input"><code><input></code></a></li><li><a href="/ja/docs/Web/HTML/Element/ins"><code><ins></code></a></li><li><a href="/ja/docs/Web/HTML/Element/kbd"><code><kbd></code></a></li><li><a href="/ja/docs/Web/HTML/Element/label"><code><label></code></a></li><li><a href="/ja/docs/Web/HTML/Element/legend"><code><legend></code></a></li><li><a href="/ja/docs/Web/HTML/Element/li"><code><li></code></a></li><li><a href="/ja/docs/Web/HTML/Element/link"><code><link></code></a></li><li><a href="/ja/docs/Web/HTML/Element/main"><code><main></code></a></li><li><a href="/ja/docs/Web/HTML/Element/map"><code><map></code></a></li><li><a href="/ja/docs/Web/HTML/Element/mark"><code><mark></code></a></li><li><a href="/ja/docs/Web/HTML/Element/marquee"><code><marquee></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/menu"><code><menu></code></a></li><li><a href="/ja/docs/Web/HTML/Element/meta"><code><meta></code></a></li><li><a href="/ja/docs/Web/HTML/Element/meter"><code><meter></code></a></li><li><a href="/ja/docs/Web/HTML/Element/nav"><code><nav></code></a></li><li><a href="/ja/docs/Web/HTML/Element/nobr"><code><nobr></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/noembed"><code><noembed></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/noframes"><code><noframes></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/noscript"><code><noscript></code></a></li><li><a href="/ja/docs/Web/HTML/Element/object"><code><object></code></a></li><li><a href="/ja/docs/Web/HTML/Element/ol"><code><ol></code></a></li><li><a href="/ja/docs/Web/HTML/Element/optgroup"><code><optgroup></code></a></li><li><a href="/ja/docs/Web/HTML/Element/option"><code><option></code></a></li><li><a href="/ja/docs/Web/HTML/Element/output"><code><output></code></a></li><li><a href="/ja/docs/Web/HTML/Element/p"><code><p></code></a></li><li><a href="/ja/docs/Web/HTML/Element/param"><code><param></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/picture"><code><picture></code></a></li><li><a href="/ja/docs/Web/HTML/Element/plaintext"><code><plaintext></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/pre"><code><pre></code></a></li><li><a href="/ja/docs/Web/HTML/Element/progress"><code><progress></code></a></li><li><a href="/ja/docs/Web/HTML/Element/q"><code><q></code></a></li><li><a href="/ja/docs/Web/HTML/Element/rb"><code><rb></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/rp"><code><rp></code></a></li><li><a href="/ja/docs/Web/HTML/Element/rt"><code><rt></code></a></li><li><a href="/ja/docs/Web/HTML/Element/rtc"><code><rtc></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/ruby"><code><ruby></code></a></li><li><a href="/ja/docs/Web/HTML/Element/s"><code><s></code></a></li><li><a href="/ja/docs/Web/HTML/Element/samp"><code><samp></code></a></li><li><a href="/ja/docs/Web/HTML/Element/script"><code><script></code></a></li><li><a href="/ja/docs/Web/HTML/Element/search"><code><search></code></a></li><li><a href="/ja/docs/Web/HTML/Element/section"><code><section></code></a></li><li><a href="/ja/docs/Web/HTML/Element/select"><code><select></code></a></li><li><a href="/ja/docs/Web/HTML/Element/slot"><code><slot></code></a></li><li><a href="/ja/docs/Web/HTML/Element/small"><code><small></code></a></li><li><a href="/ja/docs/Web/HTML/Element/source"><code><source></code></a></li><li><a href="/ja/docs/Web/HTML/Element/span"><code><span></code></a></li><li><a href="/ja/docs/Web/HTML/Element/strike"><code><strike></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/strong"><code><strong></code></a></li><li><a href="/ja/docs/Web/HTML/Element/style"><code><style></code></a></li><li><a href="/ja/docs/Web/HTML/Element/sub"><code><sub></code></a></li><li><a href="/ja/docs/Web/HTML/Element/summary"><code><summary></code></a></li><li><a href="/ja/docs/Web/HTML/Element/sup"><code><sup></code></a></li><li><a href="/ja/docs/Web/HTML/Element/table"><code><table></code></a></li><li><a href="/ja/docs/Web/HTML/Element/tbody"><code><tbody></code></a></li><li><a href="/ja/docs/Web/HTML/Element/td"><code><td></code></a></li><li><a href="/ja/docs/Web/HTML/Element/template"><code><template></code></a></li><li><a href="/ja/docs/Web/HTML/Element/textarea"><code><textarea></code></a></li><li><a href="/ja/docs/Web/HTML/Element/tfoot"><code><tfoot></code></a></li><li><a href="/ja/docs/Web/HTML/Element/th"><code><th></code></a></li><li><a href="/ja/docs/Web/HTML/Element/thead"><code><thead></code></a></li><li><a href="/ja/docs/Web/HTML/Element/time"><code><time></code></a></li><li><a href="/ja/docs/Web/HTML/Element/title"><code><title></code></a></li><li><a href="/ja/docs/Web/HTML/Element/tr"><code><tr></code></a></li><li><a href="/ja/docs/Web/HTML/Element/track"><code><track></code></a></li><li><a href="/ja/docs/Web/HTML/Element/tt"><code><tt></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Element/u"><code><u></code></a></li><li><a href="/ja/docs/Web/HTML/Element/ul"><code><ul></code></a></li><li><a href="/ja/docs/Web/HTML/Element/var"><code><var></code></a></li><li><a href="/ja/docs/Web/HTML/Element/video"><code><video></code></a></li><li><a href="/ja/docs/Web/HTML/Element/wbr"><code><wbr></code></a></li><li><a href="/ja/docs/Web/HTML/Element/xmp"><code><xmp></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">非推奨;</span> </abbr></li></ol></details></li><li class="toggle"><details><summary>グローバル属性</summary><ol><li><a href="/ja/docs/Web/HTML/Global_attributes/accesskey"><code>accesskey</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/anchor"><code>anchor</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">非標準</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Global_attributes/autocapitalize"><code>autocapitalize</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/autocorrect"><code>autocorrect</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/autofocus"><code>autofocus</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/class"><code>class</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/contenteditable"><code>contenteditable</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/data-*"><code>data-*</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/dir"><code>dir</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/draggable"><code>draggable</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/enterkeyhint"><code>enterkeyhint</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/exportparts"><code>exportparts</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/hidden"><code>hidden</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/id"><code>id</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/inert"><code>inert</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/inputmode"><code>inputmode</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/is"><code>is</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/itemid"><code>itemid</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/itemprop"><code>itemprop</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/itemref"><code>itemref</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/itemscope"><code>itemscope</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/itemtype"><code>itemtype</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/lang"><code>lang</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/nonce"><code>nonce</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/part"><code>part</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/popover"><code>popover</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/slot"><code>slot</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/spellcheck"><code>spellcheck</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/style"><code>style</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/tabindex"><code>tabindex</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/title"><code>title</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/translate"><code>translate</code></a></li><li><a href="/ja/docs/Web/HTML/Global_attributes/virtualkeyboardpolicy"><code>virtualkeyboardpolicy</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/ja/docs/Web/HTML/Global_attributes/writingsuggestions"><code>writingsuggestions</code></a></li></ol></details></li><li class="toggle"><details><summary>属性</summary><ol><li><a href="/ja/docs/Web/HTML/Attributes/accept">HTML 属性: accept</a></li><li><a href="/ja/docs/Web/HTML/Attributes/autocomplete">autocomplete</a></li><li><a href="/ja/docs/Web/HTML/Attributes/capture">HTML 属性: capture</a></li><li><a href="/ja/docs/Web/HTML/Attributes/crossorigin">HTML 属性: crossorigin</a></li><li><a href="/ja/docs/Web/HTML/Attributes/dirname">HTML 属性: dirname</a></li><li><a href="/ja/docs/Web/HTML/Attributes/disabled">HTML 属性: disabled</a></li><li><a href="/ja/docs/Web/HTML/Attributes/elementtiming">HTML 属性: elementtiming</a></li><li><a href="/ja/docs/Web/HTML/Attributes/for">HTML 属性: for</a></li><li><a href="/ja/docs/Web/HTML/Attributes/max">max</a></li><li><a href="/ja/docs/Web/HTML/Attributes/maxlength">maxlength</a></li><li><a href="/ja/docs/Web/HTML/Attributes/min">min</a></li><li><a href="/ja/docs/Web/HTML/Attributes/minlength">minlength</a></li><li><a href="/ja/docs/Web/HTML/Attributes/multiple">multiple</a></li><li><a href="/ja/docs/Web/HTML/Attributes/pattern">pattern</a></li><li><a href="/ja/docs/Web/HTML/Attributes/placeholder">HTML 属性: placeholder</a></li><li><a href="/ja/docs/Web/HTML/Attributes/readonly">HTML 属性: readonly</a></li><li><a href="/ja/docs/Web/HTML/Attributes/rel">rel</a></li><li><a href="/ja/docs/Web/HTML/Attributes/required">required</a></li><li><a href="/ja/docs/Web/HTML/Attributes/size">HTML 属性: size</a></li><li><a href="/ja/docs/Web/HTML/Attributes/step">step</a></li></ol></details></li><li class="toggle"><details><summary><code><input></code> 型</summary><ol><li><a href="/ja/docs/Web/HTML/Element/input/button"><code><input type="button"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/checkbox"><code><input type="checkbox"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/color"><code><input type="color"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/date"><code><input type="date"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/datetime-local"><code><input type="datetime-local"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/email"><code><input type="email"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/file"><code><input type="file"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/hidden"><code><input type="hidden"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/image"><code><input type="image"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/month"><code><input type="month"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/number"><code><input type="number"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/password"><code><input type="password"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/radio"><code><input type="radio"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/range"><code><input type="range"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/reset"><code><input type="reset"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/search"><code><input type="search"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/submit"><code><input type="submit"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/tel"><code><input type="tel"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/text"><code><input type="text"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/time"><code><input type="time"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/url"><code><input type="url"></code></a></li><li><a href="/ja/docs/Web/HTML/Element/input/week"><code><input type="week"></code></a></li></ol></details></li></ol></div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">この記事では</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#試してみましょう">試してみましょう</a></li><li class="document-toc-item "><a class="document-toc-link" href="#属性">属性</a></li><li class="document-toc-item "><a class="document-toc-link" href="#使用上のメモ">使用上のメモ</a></li><li class="document-toc-item "><a class="document-toc-link" href="#例">例</a></li><li class="document-toc-item "><a class="document-toc-link" href="#技術的概要">技術的概要</a></li><li class="document-toc-item "><a class="document-toc-link" href="#仕様書">仕様書</a></li><li class="document-toc-item "><a class="document-toc-link" href="#ブラウザーの互換性">ブラウザーの互換性</a></li><li class="document-toc-item "><a class="document-toc-link" href="#関連情報">関連情報</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="ja"><header><h1><dfn>: 定義要素</h1><details class="baseline-indicator high"><summary><span class="indicator" role="img" aria-label="Baseline Check"></span><div class="status-title">Baseline <span class="not-bold">Widely available</span></div><div class="browsers"><span class="engine" title="Supported in Chrome and Edge"><span class="browser chrome supported" role="img" aria-label="Chrome check"></span><span class="browser edge supported" role="img" aria-label="Edge check"></span></span><span class="engine" title="Supported in Firefox"><span class="browser firefox supported" role="img" aria-label="Firefox check"></span></span><span class="engine" title="Supported in Safari"><span class="browser safari supported" role="img" aria-label="Safari check"></span></span></div><span class="icon icon-chevron "></span></summary><div class="extra"><p>This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.</p><ul><li><a href="/ja/docs/Glossary/Baseline/Compatibility" data-glean="baseline_link_learn_more" target="_blank" class="learn-more">Learn more</a></li><li><a href="#ブラウザーの互換性" data-glean="baseline_link_bcd_table">See full compatibility</a></li><li><a href="https://survey.alchemer.com/s3/7634825/MDN-baseline-feedback?page=%2Fja%2Fdocs%2FWeb%2FHTML%2FElement%2Fdfn&level=high" data-glean="baseline_link_feedback" class="feedback-link" target="_blank" rel="noreferrer">Report feedback</a></li></ul></div></details></header><div class="section-content"><p><strong><code><dfn></code></strong> は <a href="/ja/docs/Web/HTML">HTML</a> の要素で、定義句や文の文脈の中で定義している用語を示すために用いられます。祖先である <a href="/ja/docs/Web/HTML/Element/p"><code><p></code></a> 要素、<a href="/ja/docs/Web/HTML/Element/dt"><code><dt></code></a>/<a href="/ja/docs/Web/HTML/Element/dd"><code><dd></code></a> の組み合わせ、または直近の <a href="/ja/docs/Web/HTML/Element/section"><code><section></code></a> 要素が用語の定義とみなされます。</p></div><section aria-labelledby="試してみましょう"><h2 id="試してみましょう"><a href="#試してみましょう">試してみましょう</a></h2><div class="section-content"><iframe class="interactive is-tabbed-shorter-height" height="200" src="https://interactive-examples.mdn.mozilla.net/pages/tabbed/dfn.html" title="MDN Web Docs Interactive Example" allow="clipboard-write" loading="lazy"></iframe></div></section><section aria-labelledby="属性"><h2 id="属性"><a href="#属性">属性</a></h2><div class="section-content"><p>この要素の属性は<a href="/ja/docs/Web/HTML/Global_attributes">グローバル属性</a>を含みます。</p> <p><a href="/ja/docs/Web/HTML/Global_attributes#title"><code>title</code></a> 属性は後述のとおり、通常と異なる特別な意味合いを持ちます。</p></div></section><section aria-labelledby="使用上のメモ"><h2 id="使用上のメモ"><a href="#使用上のメモ">使用上のメモ</a></h2><div class="section-content"><p><code><dfn></code> 要素の使用については、完全に明らかになっていない側面がいくつかあります。ここでそれらを説明します。</p></div></section><section aria-labelledby="定義される用語の指定"><h3 id="定義される用語の指定"><a href="#定義される用語の指定">定義される用語の指定</a></h3><div class="section-content"><p>定義される用語は、以下の規則に従います。</p> <ol> <li><code><dfn></code> 要素に <a href="/ja/docs/Web/HTML/Global_attributes#title"><code>title</code></a> 属性がある場合、 <code>title</code> 属性の値が定義される用語とみなされます。その要素の中の文字列もその用語でなければなりませんが、略語（おそらく <a href="/ja/docs/Web/HTML/Element/abbr"><code><abbr></code></a> を使用）や、用語のその他の形でも構いません。</li> <li><code><dfn></code> が単一の子要素を持ち、自分自身には何も文字列がなく、かつその子要素が <code>title</code> 属性を持つ <a href="/ja/docs/Web/HTML/Element/abbr"><code><abbr></code></a> 要素である場合は、 <code><abbr></code> 要素の <code>title</code> の値が定義する用語です。</li> <li>それ以外では、 <code><dfn></code> 要素の文字列コンテンツが定義される用語です。これは<a href="#基本的な用語の識別">以下の最初の例</a>で示します。</li> </ol> <div class="notecard note"> <p><strong>メモ:</strong> もし <code><dfn></code> 要素に <code>title</code> 属性があれば、それが定義する用語であり、それ以外の文字列ではありません。</p> </div></div></section><section aria-labelledby="dfn_要素へのリンク"><h3 id="dfn_要素へのリンク"><a href="#dfn_要素へのリンク"><code><dfn></code> 要素へのリンク</a></h3><div class="section-content"><p><code><dfn></code> 要素に <a href="/ja/docs/Web/HTML/Global_attributes#id"><code>id</code></a> 属性をつけた場合は、 <a href="/ja/docs/Web/HTML/Element/a"><code><a></code></a> 要素を使用してそこにリンクすることができます。用語の使用時にはそのようなリンクを使用して、用語のリンクをクリックすることで読者が用語の定義にすばやく移動できるようにしてください。</p> <p>これは以下の<a href="#定義へのリンク">定義へのリンク</a>の例で示します。</p></div></section><section aria-labelledby="例"><h2 id="例"><a href="#例">例</a></h2><div class="section-content"><p>様々な利用シナリオの例をいくつか見てみましょう。</p></div></section><section aria-labelledby="基本的な用語の識別"><h3 id="基本的な用語の識別"><a href="#基本的な用語の識別">基本的な用語の識別</a></h3><div class="section-content"><p>この例は、定義の中の用語の位置を識別するために素の <code><dfn></code> 要素を使用しています。</p> <h4 id="html">HTML</h4> <div class="code-example"><div class="example-header"><span class="language-name">html</span></div><pre class="brush: html notranslate"><code><p> The <strong>HTML Definition element (<dfn>&lt;dfn&gt;</dfn>)</strong> is used to indicate the term being defined within the context of a definition phrase or sentence. </p> </code></pre></div> <p><code><dfn></code> 要素に <code>title</code> がないので、 <code><dfn></code> 要素自身の文字列コンテンツが定義される用語として使用されます。</p> <h4 id="結果">結果</h4> <div class="code-example"><div class="example-header"></div><iframe class="sample-code-frame" title="Basic identification of a term sample" id="frame_basic_identification_of_a_term" width="650" height="120" src="about:blank" data-live-path="/ja/docs/Web/HTML/Element/dfn/" data-live-id="basic_identification_of_a_term" sandbox="allow-same-origin allow-scripts" loading="lazy"></iframe></div></div></section><section aria-labelledby="定義へのリンク"><h3 id="定義へのリンク"><a href="#定義へのリンク">定義へのリンク</a></h3><div class="section-content"><p>定義へのリンクを追加するには、いつも通りの方法で <a href="/ja/docs/Web/HTML/Element/a"><code><a></code></a> 要素を使ってリンクを作成します。</p> <h4 id="html_2">HTML</h4> <div class="code-example"><div class="example-header"><span class="language-name">html</span></div><pre class="brush: html notranslate"><code><p> The <strong>HTML Definition element (<dfn id="definition-dfn">&lt;dfn&gt;</dfn>)</strong> is used to indicate the term being defined within the context of a definition phrase or sentence. </p> <p> Lorem ipsum dolor sit amet, consectetur adipiscing elit. Graece donan, Latine voluptatem vocant. Confecta res esset. Duo Reges: constructio interrete. Scrupulum, inquam, abeunti; </p> <p> Because of all of that, we decided to use the <code><a href="#definition-dfn">&lt;dfn&gt;</a></code> element for this project. </p> </code></pre></div> <p>ここで <a href="/ja/docs/Web/HTML/Global_attributes#id"><code>id</code></a> 属性の <code>"definition-dfn"</code> の値をリンク先として使用して、定義を見ることができます。その後で、 <code><a></code> の <a href="/ja/docs/Web/HTML/Element/a#href"><code>href</code></a> 属性を <code>"#definition-dfn"</code> に設定して、定義に戻るリンクを設定します。</p> <h4 id="結果_2">結果</h4> <div class="code-example"><div class="example-header"></div><iframe class="sample-code-frame" title="Links to definitions sample" id="frame_links_to_definitions" width="650" height="300" src="about:blank" data-live-path="/ja/docs/Web/HTML/Element/dfn/" data-live-id="links_to_definitions" sandbox="allow-same-origin allow-scripts" loading="lazy"></iframe></div></div></section><section aria-labelledby="略語と定義の両方の使用"><h3 id="略語と定義の両方の使用"><a href="#略語と定義の両方の使用">略語と定義の両方の使用</a></h3><div class="section-content"><p>場合によっては、用語を定義する際に略語を使用したくなる場合もあるでしょう。これは <code><dfn></code> と <a href="/ja/docs/Web/HTML/Element/abbr"><code><abbr></code></a> 要素を組み合わせて、このように実現できます。</p> <h4 id="html_3">HTML</h4> <div class="code-example"><div class="example-header"><span class="language-name">html</span></div><pre class="brush: html notranslate"><code><p> The <dfn><abbr title="Hubble Space Telescope">HST</abbr></dfn> is among the most productive scientific instruments ever constructed. It has been in orbit for over 20 years, scanning the sky and returning data and photographs of unprecedented quality and detail. </p> <p> Indeed, the <abbr title="Hubble Space Telescope">HST</abbr> has arguably done more to advance science than any device ever built. </p> </code></pre></div> <p><code><abbr></code> 要素が <code><dfn></code> の中で入れ子になっています。前者は用語が略語 ("HST") であることを示し、完全な用語 ("Hubble Space Telescope") を <code>title</code> 属性で定義します。後者は略語が定義される用語であることを表します。</p> <h4 id="結果_3">結果</h4> <div class="code-example"><div class="example-header"></div><iframe class="sample-code-frame" title="Using abbreviations and definitions together sample" id="frame_using_abbreviations_and_definitions_together" width="650" height="200" src="about:blank" data-live-path="/ja/docs/Web/HTML/Element/dfn/" data-live-id="using_abbreviations_and_definitions_together" sandbox="allow-same-origin allow-scripts" loading="lazy"></iframe></div></div></section><section aria-labelledby="技術的概要"><h2 id="技術的概要"><a href="#技術的概要">技術的概要</a></h2><div class="section-content"><figure class="table-container"><table class="properties"> <tbody> <tr> <th scope="row"> <a href="/ja/docs/Web/HTML/Content_categories">コンテンツカテゴリー</a> </th> <td> <a href="/ja/docs/Web/HTML/Content_categories#フローコンテンツ">フローコンテンツ</a>, <a href="/ja/docs/Web/HTML/Content_categories#記述コンテンツ">記述コンテンツ</a>, 知覚可能コンテンツ </td> </tr> <tr> <th scope="row">許可されている内容</th> <td> <a href="/ja/docs/Web/HTML/Content_categories#記述コンテンツ">記述コンテンツ</a>、ただし <a href="/ja/docs/Web/HTML/Element/dfn" aria-current="page"><code><dfn></code></a> 要素を子孫にしてはいけません。 </td> </tr> <tr> <th scope="row">タグの省略</th> <td>なし。開始タグと終了タグの両方が必須です。</td> </tr> <tr> <th scope="row">許可されている親要素</th> <td> <a href="/ja/docs/Web/HTML/Content_categories#記述コンテンツ">記述コンテンツ</a>を受け入れるすべての要素 </td> </tr> <tr> <th scope="row">暗黙の ARIA ロール</th> <td><a href="/ja/docs/Web/Accessibility/ARIA/Roles/term_role"><code>term</code></a></td> </tr> <tr> <th scope="row">許可されている ARIA ロール</th> <td>すべて</td> </tr> <tr> <th scope="row">DOM インターフェイス</th> <td><a href="/ja/docs/Web/API/HTMLElement"><code>HTMLElement</code></a></td> </tr> </tbody> </table></figure></div></section><h2 id="仕様書"><a href="#仕様書">仕様書</a></h2><table class="standard-table"><thead><tr><th scope="col">Specification</th></tr></thead><tbody><tr><td><a href="https://html.spec.whatwg.org/multipage/text-level-semantics.html#the-dfn-element">HTML <br/><small># the-dfn-element</small></a></td></tr></tbody></table><h2 id="ブラウザーの互換性"><a href="#ブラウザーの互換性">ブラウザーの互換性</a></h2><p>BCD tables only load in the browser<noscript> with JavaScript enabled. Enable JavaScript to view data.</noscript></p><section aria-labelledby="関連情報"><h2 id="関連情報"><a href="#関連情報">関連情報</a></h2><div class="section-content"><ul> <li>定義リスト関連要素: <a href="/ja/docs/Web/HTML/Element/dl"><code><dl></code></a>, <a href="/ja/docs/Web/HTML/Element/dt"><code><dt></code></a>, <a href="/ja/docs/Web/HTML/Element/dd"><code><dd></code></a></li> <li><a href="/ja/docs/Web/HTML/Element/abbr"><code><abbr></code></a></li> </ul></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" height="162" viewBox="0 0 162 162" fill="none" role="none"><mask id="b" fill="#fff"><path d="M97.203 47.04c8.113-7.886 18.004-13.871 28.906-17.492a78 78 0 0 1 33.969-3.39c11.443 1.39 22.401 5.295 32.024 11.411s17.656 14.28 23.476 23.86c5.819 9.579 9.269 20.318 10.083 31.385a69.85 69.85 0 0 1-5.387 32.44c-4.358 10.272-11.115 19.443-19.747 26.801-8.632 7.359-18.908 12.709-30.034 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Content available under <a href="/ja/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/ja/docs/Web/HTML/Element/dfn","doc":{"body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p><strong><code><dfn></code></strong> は <a href=\"/ja/docs/Web/HTML\">HTML</a> の要素で、定義句や文の文脈の中で定義している用語を示すために用いられます。祖先である <a href=\"/ja/docs/Web/HTML/Element/p\"><code><p></code></a> 要素、<a href=\"/ja/docs/Web/HTML/Element/dt\"><code><dt></code></a>/<a href=\"/ja/docs/Web/HTML/Element/dd\"><code><dd></code></a> の組み合わせ、または直近の <a href=\"/ja/docs/Web/HTML/Element/section\"><code><section></code></a> 要素が用語の定義とみなされます。</p>"}},{"type":"prose","value":{"id":"試してみましょう","title":"試してみましょう","isH3":false,"content":"<iframe class=\"interactive is-tabbed-shorter-height\" height=\"200\" src=\"https://interactive-examples.mdn.mozilla.net/pages/tabbed/dfn.html\" title=\"MDN Web Docs Interactive Example\" allow=\"clipboard-write\" loading=\"lazy\"></iframe>"}},{"type":"prose","value":{"id":"属性","title":"属性","isH3":false,"content":"<p>この要素の属性は<a href=\"/ja/docs/Web/HTML/Global_attributes\">グローバル属性</a>を含みます。</p>\n<p><a href=\"/ja/docs/Web/HTML/Global_attributes#title\"><code>title</code></a> 属性は後述のとおり、通常と異なる特別な意味合いを持ちます。</p>"}},{"type":"prose","value":{"id":"使用上のメモ","title":"使用上のメモ","isH3":false,"content":"<p><code><dfn></code> 要素の使用については、完全に明らかになっていない側面がいくつかあります。ここでそれらを説明します。</p>"}},{"type":"prose","value":{"id":"定義される用語の指定","title":"定義される用語の指定","isH3":true,"content":"<p>定義される用語は、以下の規則に従います。</p>\n<ol>\n<li><code><dfn></code> 要素に <a href=\"/ja/docs/Web/HTML/Global_attributes#title\"><code>title</code></a> 属性がある場合、 <code>title</code> 属性の値が定義される用語とみなされます。その要素の中の文字列もその用語でなければなりませんが、略語（おそらく <a href=\"/ja/docs/Web/HTML/Element/abbr\"><code><abbr></code></a> を使用）や、用語のその他の形でも構いません。</li>\n<li><code><dfn></code> が単一の子要素を持ち、自分自身には何も文字列がなく、かつその子要素が <code>title</code> 属性を持つ <a href=\"/ja/docs/Web/HTML/Element/abbr\"><code><abbr></code></a> 要素である場合は、 <code><abbr></code> 要素の <code>title</code> の値が定義する用語です。</li>\n<li>それ以外では、 <code><dfn></code> 要素の文字列コンテンツが定義される用語です。これは<a href=\"#基本的な用語の識別\">以下の最初の例</a>で示します。</li>\n</ol>\n<div class=\"notecard note\">\n<p><strong>メモ:</strong>\nもし <code><dfn></code> 要素に <code>title</code> 属性があれば、それが定義する用語であり、それ以外の文字列ではありません。</p>\n</div>"}},{"type":"prose","value":{"id":"dfn_要素へのリンク","title":"<code><dfn></code> 要素へのリンク","isH3":true,"content":"<p><code><dfn></code> 要素に <a href=\"/ja/docs/Web/HTML/Global_attributes#id\"><code>id</code></a> 属性をつけた場合は、 <a href=\"/ja/docs/Web/HTML/Element/a\"><code><a></code></a> 要素を使用してそこにリンクすることができます。用語の使用時にはそのようなリンクを使用して、用語のリンクをクリックすることで読者が用語の定義にすばやく移動できるようにしてください。</p>\n<p>これは以下の<a href=\"#定義へのリンク\">定義へのリンク</a>の例で示します。</p>"}},{"type":"prose","value":{"id":"例","title":"例","isH3":false,"content":"<p>様々な利用シナリオの例をいくつか見てみましょう。</p>"}},{"type":"prose","value":{"id":"基本的な用語の識別","title":"基本的な用語の識別","isH3":true,"content":"<p>この例は、定義の中の用語の位置を識別するために素の <code><dfn></code> 要素を使用しています。</p>\n<h4 id=\"html\">HTML</h4>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">html</span></div><pre class=\"brush: html notranslate\"><code><p>\n The <strong>HTML Definition element (<dfn>&lt;dfn&gt;</dfn>)</strong> is used\n to indicate the term being defined within the context of a definition phrase\n or sentence.\n</p>\n</code></pre></div>\n<p><code><dfn></code> 要素に <code>title</code> がないので、 <code><dfn></code> 要素自身の文字列コンテンツが定義される用語として使用されます。</p>\n<h4 id=\"結果\">結果</h4>\n<div class=\"code-example\"><div class=\"example-header\"></div><iframe class=\"sample-code-frame\" title=\"Basic identification of a term sample\" id=\"frame_basic_identification_of_a_term\" width=\"650\" height=\"120\" src=\"about:blank\" data-live-path=\"/ja/docs/Web/HTML/Element/dfn/\" data-live-id=\"basic_identification_of_a_term\" sandbox=\"allow-same-origin allow-scripts\" loading=\"lazy\"></iframe></div>"}},{"type":"prose","value":{"id":"定義へのリンク","title":"定義へのリンク","isH3":true,"content":"<p>定義へのリンクを追加するには、いつも通りの方法で <a href=\"/ja/docs/Web/HTML/Element/a\"><code><a></code></a> 要素を使ってリンクを作成します。</p>\n<h4 id=\"html_2\">HTML</h4>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">html</span></div><pre class=\"brush: html notranslate\"><code><p>\n The\n <strong>HTML Definition element (<dfn id=\"definition-dfn\">&lt;dfn&gt;</dfn>)</strong>\n is used to indicate the term being defined within the context of a definition\n phrase or sentence.\n</p>\n\n<p>\n Lorem ipsum dolor sit amet, consectetur adipiscing elit. Graece donan, Latine\n voluptatem vocant. Confecta res esset. Duo Reges: constructio interrete.\n Scrupulum, inquam, abeunti;\n</p>\n\n<p>\n Because of all of that, we decided to use the\n <code><a href=\"#definition-dfn\">&lt;dfn&gt;</a></code> element for this\n project.\n</p>\n</code></pre></div>\n<p>ここで <a href=\"/ja/docs/Web/HTML/Global_attributes#id\"><code>id</code></a> 属性の <code>\"definition-dfn\"</code> の値をリンク先として使用して、定義を見ることができます。その後で、 <code><a></code> の <a href=\"/ja/docs/Web/HTML/Element/a#href\"><code>href</code></a> 属性を <code>\"#definition-dfn\"</code> に設定して、定義に戻るリンクを設定します。</p>\n<h4 id=\"結果_2\">結果</h4>\n<div class=\"code-example\"><div class=\"example-header\"></div><iframe class=\"sample-code-frame\" title=\"Links to definitions sample\" id=\"frame_links_to_definitions\" width=\"650\" height=\"300\" src=\"about:blank\" data-live-path=\"/ja/docs/Web/HTML/Element/dfn/\" data-live-id=\"links_to_definitions\" sandbox=\"allow-same-origin allow-scripts\" loading=\"lazy\"></iframe></div>"}},{"type":"prose","value":{"id":"略語と定義の両方の使用","title":"略語と定義の両方の使用","isH3":true,"content":"<p>場合によっては、用語を定義する際に略語を使用したくなる場合もあるでしょう。これは <code><dfn></code> と <a href=\"/ja/docs/Web/HTML/Element/abbr\"><code><abbr></code></a> 要素を組み合わせて、このように実現できます。</p>\n<h4 id=\"html_3\">HTML</h4>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">html</span></div><pre class=\"brush: html notranslate\"><code><p>\n The <dfn><abbr title=\"Hubble Space Telescope\">HST</abbr></dfn> is among the\n most productive scientific instruments ever constructed. It has been in orbit\n for over 20 years, scanning the sky and returning data and photographs of\n unprecedented quality and detail.\n</p>\n\n<p>\n Indeed, the <abbr title=\"Hubble Space Telescope\">HST</abbr> has arguably done\n more to advance science than any device ever built.\n</p>\n</code></pre></div>\n<p><code><abbr></code> 要素が <code><dfn></code> の中で入れ子になっています。前者は用語が略語 (\"HST\") であることを示し、完全な用語 (\"Hubble Space Telescope\") を <code>title</code> 属性で定義します。後者は略語が定義される用語であることを表します。</p>\n<h4 id=\"結果_3\">結果</h4>\n<div class=\"code-example\"><div class=\"example-header\"></div><iframe class=\"sample-code-frame\" title=\"Using abbreviations and definitions together sample\" id=\"frame_using_abbreviations_and_definitions_together\" width=\"650\" height=\"200\" src=\"about:blank\" data-live-path=\"/ja/docs/Web/HTML/Element/dfn/\" data-live-id=\"using_abbreviations_and_definitions_together\" sandbox=\"allow-same-origin allow-scripts\" loading=\"lazy\"></iframe></div>"}},{"type":"prose","value":{"id":"技術的概要","title":"技術的概要","isH3":false,"content":"<figure class=\"table-container\"><table class=\"properties\">\n <tbody>\n <tr>\n <th scope=\"row\">\n <a href=\"/ja/docs/Web/HTML/Content_categories\">コンテンツカテゴリー</a>\n </th>\n <td>\n <a href=\"/ja/docs/Web/HTML/Content_categories#フローコンテンツ\">フローコンテンツ</a>,\n <a href=\"/ja/docs/Web/HTML/Content_categories#記述コンテンツ\">記述コンテンツ</a>, 知覚可能コンテンツ\n </td>\n </tr>\n <tr>\n <th scope=\"row\">許可されている内容</th>\n <td>\n <a href=\"/ja/docs/Web/HTML/Content_categories#記述コンテンツ\">記述コンテンツ</a>、ただし <a href=\"/ja/docs/Web/HTML/Element/dfn\" aria-current=\"page\"><code><dfn></code></a> 要素を子孫にしてはいけません。\n </td>\n </tr>\n <tr>\n <th scope=\"row\">タグの省略</th>\n <td>なし。開始タグと終了タグの両方が必須です。</td>\n </tr>\n <tr>\n <th scope=\"row\">許可されている親要素</th>\n <td>\n <a href=\"/ja/docs/Web/HTML/Content_categories#記述コンテンツ\">記述コンテンツ</a>を受け入れるすべての要素\n </td>\n </tr>\n <tr>\n <th scope=\"row\">暗黙の ARIA ロール</th>\n <td><a href=\"/ja/docs/Web/Accessibility/ARIA/Roles/term_role\"><code>term</code></a></td>\n </tr>\n <tr>\n <th scope=\"row\">許可されている ARIA ロール</th>\n <td>すべて</td>\n </tr>\n <tr>\n <th scope=\"row\">DOM インターフェイス</th>\n <td><a href=\"/ja/docs/Web/API/HTMLElement\"><code>HTMLElement</code></a></td>\n </tr>\n </tbody>\n</table></figure>"}},{"type":"specifications","value":{"id":"仕様書","title":"仕様書","isH3":false,"specifications":[{"bcdSpecificationURL":"https://html.spec.whatwg.org/multipage/text-level-semantics.html#the-dfn-element","title":"HTML"}],"query":"html.elements.dfn"}},{"type":"browser_compatibility","value":{"id":"ブラウザーの互換性","title":"ブラウザーの互換性","isH3":false,"query":"html.elements.dfn"}},{"type":"prose","value":{"id":"関連情報","title":"関連情報","isH3":false,"content":"<ul>\n<li>定義リスト関連要素: <a href=\"/ja/docs/Web/HTML/Element/dl\"><code><dl></code></a>, <a href=\"/ja/docs/Web/HTML/Element/dt\"><code><dt></code></a>, <a href=\"/ja/docs/Web/HTML/Element/dd\"><code><dd></code></a></li>\n<li><a href=\"/ja/docs/Web/HTML/Element/abbr\"><code><abbr></code></a></li>\n</ul>"}}],"isActive":true,"isMarkdown":true,"isTranslated":true,"locale":"ja","mdn_url":"/ja/docs/Web/HTML/Element/dfn","modified":"2024-08-21T12:49:39.000Z","native":"日本語","noIndexing":false,"other_translations":[{"locale":"en-US","title":"<dfn>: The Definition element","native":"English (US)"},{"locale":"de","title":"<dfn>: Das Definitionselement","native":"Deutsch"},{"locale":"es","title":"dfn","native":"Español"},{"locale":"fr","title":"<dfn> : l'élément de définition","native":"Français"},{"locale":"ko","title":"<dfn>: 정의 요소","native":"한국어"},{"locale":"pt-BR","title":"<dfn>","native":"Português (do Brasil)"},{"locale":"ru","title":"<dfn>: Элемент определения","native":"Русский"},{"locale":"zh-CN","title":"<dfn>","native":"中文 (简体)"},{"locale":"zh-TW","title":"<dfn>：定義元素","native":"正體中文 (繁體)"}],"pageTitle":"<dfn>: 定義要素 - HTML: ハイパーテキストマークアップ言語 | MDN","parents":[{"uri":"/ja/docs/Web","title":"開発者向けのウェブ技術"},{"uri":"/ja/docs/Web/HTML","title":"HTML"},{"uri":"/ja/docs/Web/HTML/Element","title":"HTML 要素リファレンス"},{"uri":"/ja/docs/Web/HTML/Element/dfn","title":"<dfn>"}],"popularity":null,"short_title":"<dfn>","sidebarHTML":"<ol><li class=\"section\"><a href=\"/ja/docs/Web/HTML\">HTML</a></li><li class=\"toggle\"><details><summary>チュートリアル</summary><ol><li><a href=\"/ja/docs/Learn_web_development/Getting_started/Your_first_website/Creating_the_content\">初めてのウェブサイト: コンテンツの作成</a></li><li class=\"toggle\"><details><summary><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content\">HTML によるコンテンツの構造化</a></summary><ol><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Basic_HTML_syntax\">基本的な HTML の構文</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Webpage_metadata\">ヘッド部には何が入る? ウェブページのメタデータ</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs\">HTML の見出しと段落</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance\">強調と重要性</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Lists\">リスト</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Structuring_documents\">文書とウェブサイトの構造</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features\">高度なテキスト装飾</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Creating_links\">リンクの作成</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter\">課題: 手紙のマークアップ</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content\">課題: コンテンツのページの構造化</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/HTML_images\">HTML の画像</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio\">動画と音声のコンテンツ</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Mozilla_splash_page\">Mozilla のスプラッシュページ</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics\">HTML の表の基本</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Table_accessibility\">HTML 表のアクセシビリティ</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Planet_data_table\">課題: 惑星データの構造化</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/HTML_forms\">HTML におけるフォームとボタン</a></li><li><a href=\"/ja/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML\">HTML のデバッグ</a></li></ol></details></li></ol></details></li><li class=\"toggle\"><details><summary>ガイド</summary><ol><li><a href=\"/ja/docs/Web/HTML/Content_categories\">コンテンツカテゴリー</a></li><li><a href=\"/ja/docs/Glossary/Block-level_content\">ブロックレベル要素</a></li><li><a href=\"/ja/docs/Glossary/Inline-level_content\">インライン要素</a></li><li><a href=\"/ja/docs/Web/HTML/Quirks_Mode_and_Standards_Mode\">互換モードと標準モード</a></li><li><a href=\"/ja/docs/Web/HTML/Date_and_time_formats\">HTML で使用される日付と時刻の形式</a></li><li><a href=\"/ja/docs/Web/HTML/Constraint_validation\">制約検証</a></li><li><a href=\"/ja/docs/Web/HTML/Microdata\">Microdata</a></li><li><a href=\"/ja/docs/Web/HTML/microformats\">Microformats</a></li><li><a href=\"/ja/docs/Web/HTML/Viewport_meta_tag\">ビューポートメタタグ</a></li><li><a href=\"/ja/docs/Web/HTML/CORS_enabled_image\">別オリジンの画像とキャンバスを利用可能にする</a></li></ol></details></li><li class=\"section\"><a href=\"/ja/docs/Web/HTML/Reference\">リファレンス</a></li><li class=\"toggle\"><details open=\"\"><summary>HTML 要素</summary><ol><li><a href=\"/ja/docs/Web/HTML/Element/a\"><code><a></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/abbr\"><code><abbr></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/acronym\"><code><acronym></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/address\"><code><address></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/area\"><code><area></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/article\"><code><article></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/aside\"><code><aside></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/audio\"><code><audio></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/b\"><code><b></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/base\"><code><base></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/bdi\"><code><bdi></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/bdo\"><code><bdo></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/big\"><code><big></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/blockquote\"><code><blockquote></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/body\"><code><body></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/br\"><code><br></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/button\"><code><button></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/canvas\"><code><canvas></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/caption\"><code><caption></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/center\"><code><center></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/cite\"><code><cite></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/code\"><code><code></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/col\"><code><col></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/colgroup\"><code><colgroup></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/data\"><code><data></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/datalist\"><code><datalist></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/dd\"><code><dd></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/del\"><code><del></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/details\"><code><details></code></a></li><li><em><a href=\"/ja/docs/Web/HTML/Element/dfn\" aria-current=\"page\"><code><dfn></code></a></em></li><li><a href=\"/ja/docs/Web/HTML/Element/dialog\"><code><dialog></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/dir\"><code><dir></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/div\"><code><div></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/dl\"><code><dl></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/dt\"><code><dt></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/em\"><code><em></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/embed\"><code><embed></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/fencedframe\" class=\"only-in-en-us\"><code><fencedframe></code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n<span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/fieldset\"><code><fieldset></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/figcaption\"><code><figcaption></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/figure\"><code><figure></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/font\"><code><font></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/footer\"><code><footer></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/form\"><code><form></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/frame\"><code><frame></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/frameset\"><code><frameset></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/Heading_Elements\"><code><h1></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/head\"><code><head></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/header\"><code><header></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/hgroup\"><code><hgroup></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/hr\"><code><hr></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/html\"><code><html></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/i\"><code><i></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/iframe\"><code><iframe></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/img\"><code><img></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input\"><code><input></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/ins\"><code><ins></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/kbd\"><code><kbd></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/label\"><code><label></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/legend\"><code><legend></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/li\"><code><li></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/link\"><code><link></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/main\"><code><main></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/map\"><code><map></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/mark\"><code><mark></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/marquee\"><code><marquee></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/menu\"><code><menu></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/meta\"><code><meta></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/meter\"><code><meter></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/nav\"><code><nav></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/nobr\"><code><nobr></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/noembed\"><code><noembed></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/noframes\"><code><noframes></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/noscript\"><code><noscript></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/object\"><code><object></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/ol\"><code><ol></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/optgroup\"><code><optgroup></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/option\"><code><option></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/output\"><code><output></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/p\"><code><p></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/param\"><code><param></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/picture\"><code><picture></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/plaintext\"><code><plaintext></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/pre\"><code><pre></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/progress\"><code><progress></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/q\"><code><q></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/rb\"><code><rb></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/rp\"><code><rp></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/rt\"><code><rt></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/rtc\"><code><rtc></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/ruby\"><code><ruby></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/s\"><code><s></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/samp\"><code><samp></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/script\"><code><script></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/search\"><code><search></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/section\"><code><section></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/select\"><code><select></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/slot\"><code><slot></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/small\"><code><small></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/source\"><code><source></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/span\"><code><span></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/strike\"><code><strike></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/strong\"><code><strong></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/style\"><code><style></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/sub\"><code><sub></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/summary\"><code><summary></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/sup\"><code><sup></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/table\"><code><table></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/tbody\"><code><tbody></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/td\"><code><td></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/template\"><code><template></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/textarea\"><code><textarea></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/tfoot\"><code><tfoot></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/th\"><code><th></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/thead\"><code><thead></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/time\"><code><time></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/title\"><code><title></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/tr\"><code><tr></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/track\"><code><track></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/tt\"><code><tt></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Element/u\"><code><u></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/ul\"><code><ul></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/var\"><code><var></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/video\"><code><video></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/wbr\"><code><wbr></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/xmp\"><code><xmp></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">非推奨;</span>\n</abbr></li></ol></details></li><li class=\"toggle\"><details><summary>グローバル属性</summary><ol><li><a href=\"/ja/docs/Web/HTML/Global_attributes/accesskey\"><code>accesskey</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/anchor\"><code>anchor</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n<span class=\"visually-hidden\">Experimental</span>\n</abbr><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n<span class=\"visually-hidden\">非標準</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/autocapitalize\"><code>autocapitalize</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/autocorrect\"><code>autocorrect</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/autofocus\"><code>autofocus</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/class\"><code>class</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/contenteditable\"><code>contenteditable</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/data-*\"><code>data-*</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/dir\"><code>dir</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/draggable\"><code>draggable</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/enterkeyhint\"><code>enterkeyhint</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/exportparts\"><code>exportparts</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/hidden\"><code>hidden</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/id\"><code>id</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/inert\"><code>inert</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/inputmode\"><code>inputmode</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/is\"><code>is</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/itemid\"><code>itemid</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/itemprop\"><code>itemprop</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/itemref\"><code>itemref</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/itemscope\"><code>itemscope</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/itemtype\"><code>itemtype</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/lang\"><code>lang</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/nonce\"><code>nonce</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/part\"><code>part</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/popover\"><code>popover</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/slot\"><code>slot</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/spellcheck\"><code>spellcheck</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/style\"><code>style</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/tabindex\"><code>tabindex</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/title\"><code>title</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/translate\"><code>translate</code></a></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/virtualkeyboardpolicy\"><code>virtualkeyboardpolicy</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n<span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/ja/docs/Web/HTML/Global_attributes/writingsuggestions\"><code>writingsuggestions</code></a></li></ol></details></li><li class=\"toggle\"><details><summary>属性</summary><ol><li><a href=\"/ja/docs/Web/HTML/Attributes/accept\">HTML 属性: accept</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/autocomplete\">autocomplete</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/capture\">HTML 属性: capture</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/crossorigin\">HTML 属性: crossorigin</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/dirname\">HTML 属性: dirname</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/disabled\">HTML 属性: disabled</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/elementtiming\">HTML 属性: elementtiming</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/for\">HTML 属性: for</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/max\">max</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/maxlength\">maxlength</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/min\">min</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/minlength\">minlength</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/multiple\">multiple</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/pattern\">pattern</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/placeholder\">HTML 属性: placeholder</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/readonly\">HTML 属性: readonly</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/rel\">rel</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/required\">required</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/size\">HTML 属性: size</a></li><li><a href=\"/ja/docs/Web/HTML/Attributes/step\">step</a></li></ol></details></li><li class=\"toggle\"><details><summary><code><input></code> 型</summary><ol><li><a href=\"/ja/docs/Web/HTML/Element/input/button\"><code><input type=\"button\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/checkbox\"><code><input type=\"checkbox\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/color\"><code><input type=\"color\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/date\"><code><input type=\"date\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/datetime-local\"><code><input type=\"datetime-local\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/email\"><code><input type=\"email\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/file\"><code><input type=\"file\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/hidden\"><code><input type=\"hidden\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/image\"><code><input type=\"image\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/month\"><code><input type=\"month\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/number\"><code><input type=\"number\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/password\"><code><input type=\"password\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/radio\"><code><input type=\"radio\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/range\"><code><input type=\"range\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/reset\"><code><input type=\"reset\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/search\"><code><input type=\"search\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/submit\"><code><input type=\"submit\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/tel\"><code><input type=\"tel\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/text\"><code><input type=\"text\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/time\"><code><input type=\"time\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/url\"><code><input type=\"url\"></code></a></li><li><a href=\"/ja/docs/Web/HTML/Element/input/week\"><code><input type=\"week\"></code></a></li></ol></details></li></ol>","source":{"folder":"ja/web/html/element/dfn","github_url":"https://github.com/mdn/translated-content/blob/main/files/ja/web/html/element/dfn/index.md","last_commit_url":"https://github.com/mdn/translated-content/commit/f51679ea54e28b3cbda80ce99da358c990f46eff","filename":"index.md"},"summary":"<dfn> は HTML の要素で、定義句や文の文脈の中で定義している用語を示すために用いられます。祖先である <p> 要素、<dt>/<dd> の組み合わせ、または直近の <section> 要素が用語の定義とみなされます。","title":"<dfn>: 定義要素","toc":[{"text":"試してみましょう","id":"試してみましょう"},{"text":"属性","id":"属性"},{"text":"使用上のメモ","id":"使用上のメモ"},{"text":"例","id":"例"},{"text":"技術的概要","id":"技術的概要"},{"text":"仕様書","id":"仕様書"},{"text":"ブラウザーの互換性","id":"ブラウザーの互換性"},{"text":"関連情報","id":"関連情報"}],"baseline":{"baseline":"high","baseline_low_date":"2015-07-29","baseline_high_date":"2018-01-29","support":{"chrome":"15","chrome_android":"18","edge":"12","firefox":"1","firefox_android":"4","safari":"6","safari_ios":"6"}},"browserCompat":["html.elements.dfn"],"pageType":"html-element"}}</script></body></html>