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Ab initio - Wikipedia
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vector-toc-level-2"> <a class="vector-toc-link" href="#Other_uses"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Other uses</span> </div> </a> <ul id="toc-Other_uses-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 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href="https://bn.wikipedia.org/wiki/%E0%A6%85%E0%A7%8D%E0%A6%AF%E0%A6%BE%E0%A6%AC_%E0%A6%87%E0%A6%A8%E0%A6%BF%E0%A6%B6%E0%A6%BF%E0%A6%AF%E0%A6%BC%E0%A7%8B" title="অ্যাব ইনিশিয়ো – Bangla" lang="bn" hreflang="bn" data-title="অ্যাব ইনিশিয়ো" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Ab_initio" title="Ab initio – Bosnian" lang="bs" hreflang="bs" data-title="Ab initio" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Ab_initio" title="Ab initio – Welsh" lang="cy" hreflang="cy" data-title="Ab initio" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Ab_initio" title="Ab initio – German" lang="de" hreflang="de" data-title="Ab initio" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Ab_initio" title="Ab initio – Spanish" lang="es" hreflang="es" data-title="Ab initio" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Ab_initio" title="Ab initio – Basque" lang="eu" hreflang="eu" data-title="Ab initio" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Ab_initio" title="Ab initio – French" lang="fr" hreflang="fr" data-title="Ab initio" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Ab_initio" title="Ab initio – Italian" lang="it" hreflang="it" data-title="Ab initio" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/Ab_initio" title="Ab initio – Japanese" lang="ja" hreflang="ja" data-title="Ab initio" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Ab_initio" title="Ab initio – Romanian" lang="ro" hreflang="ro" data-title="Ab initio" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/Ab_initio" title="Ab initio – Russian" lang="ru" hreflang="ru" data-title="Ab initio" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Ab_initio" title="Ab initio – Turkish" lang="tr" hreflang="tr" data-title="Ab initio" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/Ab_initio" title="Ab initio – Ukrainian" lang="uk" hreflang="uk" data-title="Ab initio" 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<div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Latin term meaning "from the beginning"</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">For other uses, see <a href="/wiki/Ab_initio_(disambiguation)" class="mw-disambig" title="Ab initio (disambiguation)">Ab initio (disambiguation)</a>.</div> <p> <b><span title="Latin-language text"><i lang="la">Ab initio</i></span></b> (<span class="rt-commentedText nowrap"><span class="IPA nopopups noexcerpt" lang="en-fonipa"><a href="/wiki/Help:IPA/English" title="Help:IPA/English">/<span style="border-bottom:1px dotted"><span title="/ˌ/: secondary stress follows">ˌ</span><span title="/æ/: 'a' in 'bad'">æ</span><span title="'b' in 'buy'">b</span></span><span class="wrap"> </span><span style="border-bottom:1px dotted"><span title="/ɪ/: 'i' in 'kit'">ɪ</span><span title="/ˈ/: primary stress follows">ˈ</span><span title="'n' in 'nigh'">n</span><span title="/ɪ/: 'i' in 'kit'">ɪ</span><span title="/ʃ/: 'sh' in 'shy'">ʃ</span><span title="/i/: 'y' in 'happy'">i</span><span title="/oʊ/: 'o' in 'code'">oʊ</span></span>/</a></span></span> <a href="/wiki/Help:Pronunciation_respelling_key" title="Help:Pronunciation respelling key"><i title="English pronunciation respelling"><span style="font-size:90%">AB</span> in-<span style="font-size:90%">ISH</span>-ee-oh</i></a>)<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> is a Latin term meaning "from the beginning" and is derived from the Latin <span title="Latin-language text"><i lang="la">ab</i></span> ("from") + <span title="Latin-language text"><i lang="la">initio</i></span>, <a href="/wiki/Ablative_case" title="Ablative case">ablative</a> <a href="/wiki/Grammatical_number" title="Grammatical number">singular</a> of <span title="Latin-language text"><i lang="la">initium</i></span> ("beginning"). </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Etymology">Etymology</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ab_initio&action=edit&section=1" title="Edit section: Etymology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><abbr title="circa">c.</abbr><span style="white-space:nowrap;"> 1600</span>, from Latin, literally "from the beginning", from ablative case of <span title="Latin-language text"><i lang="la">initium</i></span> "entrance", "beginning", related to verb <span title="Latin-language text"><i lang="la">inire</i></span> "to go into", "enter upon", "begin".<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Uses">Uses</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ab_initio&action=edit&section=2" title="Edit section: Uses"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><i>Ab initio</i> (abbreviation: <i>ab init.</i>) is used in several contexts, including the following: </p> <div class="mw-heading mw-heading3"><h3 id="Law">Law</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ab_initio&action=edit&section=3" title="Edit section: Law"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In <a href="/wiki/Law" title="Law">law</a>, <i>ab initio</i> refers to something being the case from the start or from the instant of the act rather than from when the court declared it so. For instance, the term "void <i>ab initio</i>" means "to be treated as invalid from the outset." E.g., in many <a href="/wiki/Jurisdiction" title="Jurisdiction">jurisdictions</a>, if a person signs a contract under duress, that contract is treated as being "void <i>ab initio</i>". </p><p>Typically, documents or acts which are <a href="/wiki/Void_(law)" title="Void (law)">void</a> <i>ab initio</i> cannot be fixed and if a jurisdiction, a document, or an act is so declared at law to be void <i>ab initio</i>, the parties are returned to their respective positions that they were at the beginning of the event. </p><p>"Void <i>ab initio</i>" is often contrasted with "voidable" <i>in futuro</i>, such documents which become void only as of the date of a certain event or of the judicial declaration to that effect. For example, termination of a contract only operates <i>in futuro</i>. </p><p>An insurer facing a claim from an insured who had deceived the insurer on a material fact would claim that the insurance contract was void <i>ab initio</i>; it was null and void from the beginning and that since there was no legally enforceable contract, the insurer ought not to have to pay.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Science_and_engineering">Science and engineering</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ab_initio&action=edit&section=4" title="Edit section: Science and engineering"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In general, a calculation is said to be <i>ab initio</i> (or "from <a href="/wiki/First_principle#In_physics" title="First principle">first principles</a>") if it relies on basic and established laws of nature without additional assumptions or special models. </p><p>For example, an <i>ab initio</i> calculation of the properties of liquid water might start with the properties of the constituent hydrogen and oxygen atoms and the laws of electrostatics and quantum mechanics. From these basics, the properties of isolated individual water molecules would be derived, followed by computations of the interactions of larger and larger groups of water molecules, until the bulk properties of water had been determined. This in contrast to an approach that uses approximations (which could allow for easier computations) that have no direct link to these first principles. </p> <ul><li><a href="/wiki/Documentation" title="Documentation">Documentation</a> of a process is said to be <i>ab initio</i> (or <i><a href="https://en.wiktionary.org/wiki/from_scratch" class="extiw" title="wikt:from scratch">from scratch</a></i>, or <i><a href="https://en.wiktionary.org/wiki/from_the_ground_up" class="extiw" title="wikt:from the ground up">from the ground up</a></i>) if the documentation shows how to set up and complete the process from basic materials (to which a competent practitioner is expected to have access) without prior special preparation.</li> <li>In <a href="/wiki/Nuclear_physics" title="Nuclear physics">nuclear physics</a>, the mass-energy of different nuclei can be determined with <a href="/wiki/Ab_initio_methods_(nuclear_physics)" title="Ab initio methods (nuclear physics)"><i>ab initio</i> methods</a> by solving the <a href="/wiki/Schr%C3%B6dinger_equation" title="Schrödinger equation">Schrödinger equation</a> over all particles.</li> <li>Likewise in <a href="/wiki/Chemistry" title="Chemistry">chemistry</a>, this refers to <a href="/wiki/Ab_initio_quantum_chemistry_methods" title="Ab initio quantum chemistry methods"><i>ab initio</i> quantum chemistry methods</a>.</li> <li>In <a href="/wiki/Biophysics" title="Biophysics">biophysics</a>, this refers to a method for the prediction of protein structures in protein folding.</li> <li>In <a href="/wiki/Bioinformatics" title="Bioinformatics">bioinformatics</a>, <i>ab initio</i> (or <i><a href="https://en.wiktionary.org/wiki/de_novo" class="extiw" title="wikt:de novo">de novo</a></i>) methods make predictions about biological features using only a computational model without extrinsic comparison to existing data.</li> <li>In <a href="/wiki/Aviation" title="Aviation">aviation</a>, this refers to the first stage of flight training.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Other_uses">Other uses</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ab_initio&action=edit&section=5" title="Edit section: Other uses"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>In <a href="/wiki/Literature" title="Literature">literature</a>, a story told <i>ab initio</i> is told from the beginning; <a href="/wiki/Horace" title="Horace">Horace</a> called this method <i><a href="/wiki/Ab_ovo" title="Ab ovo">ab ovo</a></i> ('from the egg'). This is as opposed to <i><a href="/wiki/In_medias_res" title="In medias res">in medias res</a></i> (in the middle of the story).</li> <li>In learning a subject or foreign language, <i>ab initio</i> refers to study without previous knowledge or assumptions.</li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ab_initio&action=edit&section=6" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239009302">.mw-parser-output .portalbox{padding:0;margin:0.5em 0;display:table;box-sizing:border-box;max-width:175px;list-style:none}.mw-parser-output .portalborder{border:1px solid var(--border-color-base,#a2a9b1);padding:0.1em;background:var(--background-color-neutral-subtle,#f8f9fa)}.mw-parser-output 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srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Balance%2C_by_David.svg/46px-Balance%2C_by_David.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/17/Balance%2C_by_David.svg/61px-Balance%2C_by_David.svg.png 2x" data-file-width="606" data-file-height="558" /></a></span></span><span class="portalbox-link"><a href="/wiki/Portal:Law" title="Portal:Law">Law portal</a></span></li></ul> <ul><li><i><a href="/wiki/A_priori" class="mw-redirect" title="A priori">A priori</a></i></li> <li><a href="/wiki/Abatement_ab_initio" title="Abatement ab initio">Abatement <i>ab initio</i></a></li> <li><i><a href="/wiki/Ad_fontes" title="Ad fontes">Ad fontes</a></i></li> <li><a href="/wiki/List_of_legal_Latin_terms" class="mw-redirect" title="List of legal Latin terms">List of legal Latin terms</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ab_initio&action=edit&section=7" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><a href="/wiki/Merriam-Webster%27s_Collegiate_Dictionary" class="mw-redirect" title="Merriam-Webster's Collegiate Dictionary">Merriam-Webster's Collegiate Dictionary</a></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.etymonline.com/index.php?term=ab+initio">"Etymology for ab initio"</a>. <i>etymonline.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">7 February</span> 2010</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=etymonline.com&rft.atitle=Etymology+for+ab+initio&rft_id=http%3A%2F%2Fwww.etymonline.com%2Findex.php%3Fterm%3Dab%2Binitio&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAb+initio" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20100214123816/http://duhaime.org/LegalDictionary/A/AbInitio.aspx">"Legal definition at Duhaime.org"</a>. <i>duhaime.org</i>. Archived from <a rel="nofollow" class="external text" href="http://duhaime.org/legaldictionary/a/abinitio.aspx">the original</a> on 14 February 2010<span class="reference-accessdate">. Retrieved <span class="nowrap">7 February</span> 2010</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=duhaime.org&rft.atitle=Legal+definition+at+Duhaime.org&rft_id=http%3A%2F%2Fduhaime.org%2Flegaldictionary%2Fa%2Fabinitio.aspx&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAb+initio" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ab_initio&action=edit&section=8" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1237033735">@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}</style><div class="side-box side-box-right plainlinks sistersitebox"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/40px-Wiktionary-logo-en-v2.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/60px-Wiktionary-logo-en-v2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/80px-Wiktionary-logo-en-v2.svg.png 2x" data-file-width="512" data-file-height="512" /></span></span></div> <div class="side-box-text plainlist">Look up <i><b><a href="https://en.wiktionary.org/wiki/Special:Search/ab_initio" class="extiw" title="wiktionary:Special:Search/ab initio">ab initio</a></b></i> in Wiktionary, the free dictionary.</div></div> </div> <ul><li><a rel="nofollow" class="external text" href="http://dictionary.reference.com/cite.html?qh=ab+initio&ia=mwlaw">Definition at Dictionary.com</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20121025135828/http://dictionary.reference.com/cite.html?qh=ab+initio&ia=mwlaw">Archived</a> 2012-10-25 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li></ul> <!-- NewPP limit report Parsed by mw‐web.codfw.main‐f69cdc8f6‐hhmqd Cached time: 20241122152858 Cache expiry: 2592000 Reduced expiry: false Complications: [vary‐revision‐sha1, show‐toc] CPU time usage: 0.390 seconds Real time usage: 0.499 seconds Preprocessor visited node count: 672/1000000 Post‐expand include size: 10820/2097152 bytes Template argument size: 716/2097152 bytes Highest expansion depth: 9/100 Expensive parser function count: 3/500 Unstrip recursion depth: 1/20 Unstrip post‐expand size: 10840/5000000 bytes Lua time usage: 0.285/10.000 seconds Lua memory usage: 13531574/52428800 bytes Number of Wikibase entities loaded: 0/400 --> <!-- Transclusion expansion time report (%,ms,calls,template) 100.00% 471.053 1 -total 30.03% 141.445 6 Template:Lang 26.54% 124.998 1 Template:Reflist 21.43% 100.959 2 Template:Cite_web 14.59% 68.750 1 Template:Short_description 8.47% 39.888 2 Template:Pagetype 6.80% 32.019 1 Template:IPAc-en 5.92% 27.879 1 Template:Wiktionary 5.43% 25.581 1 Template:Sister_project 5.19% 24.435 1 Template:About --> <!-- Saved in parser cache with key enwiki:pcache:idhash:26084631-0!canonical and timestamp 20241122152858 and revision id 1230005924. 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