af·​fi·​da·​vit | \ ˌa-fə-ˈdā-vət How to pronounce affidavit (audio) \

Definition of affidavit

: a sworn statement in writing made especially under oath or on affirmation (see affirmation sense 2) before an authorized magistrate or officer The witness's affidavit was presented to the court as evidence.

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Promises, Promises: The History of Affidavit, Affiance, & Fiancé

Affidavit refers to a written promise, and its Latin roots connect it to another kind of promise in English. It comes from a past tense form of the Latin verb affidare, meaning “to pledge”; in Latin, affidavit translates to “he or she has made a pledge.”

Affidare is also the root of affiance, an archaic English noun meaning “trust, faith, confidence,” “marriage contract or promise,” or a meaning that has completely fallen from use, “close or intimate relationship.” More familiar to modern English speakers is the verb affiance, meaning “to promise in marriage” or “to betroth.” It usually appears as a fancy-sounding participial adjective:

I like to give affianced friends a copy of Rebecca Mead’s book “One Perfect Day,” which exposes the ridiculous wedding industry.
—Mollie Hemingway, The Federalist, 7 October 2014

Affiance came through French to English in the 14th century, and, nearly 500 years later, the related French words fiancé and fiancée were added to English. Etymologically speaking, a fiancé or fiancée is a “promised one.”

Did You Know?

In Latin, affidavit means "he (she) has sworn an oath", and an affidavit is always a sworn written document. If it contains a lie, the person making it may be prosecuted. Affidavits are often used in court when it isn't possible for someone to appear in person. Police officers must usually file an affidavit with a judge to get a search warrant. Affidavits (unlike similar signed statements called depositions) are usually made without an opposing lawyer being present and able to ask questions.

Examples of affidavit in a Sentence

We have a signed affidavit stating that the two men were seen entering the building.
Recent Examples on the Web Security cameras at the motel captured the moment Lewis was gunned down, according to Johnson’s arrest warrant affidavit. Jacob Beltran, San Antonio Express-News, "Man arrested in April slaying at East Side motel," 27 Mar. 2021 The affidavit lists the address for Givens, 24, as 4900 Marie P. DeBartolo Way — the address for Levi’s Stadium. Michael Williams, San Francisco Chronicle, "49ers defensive lineman Kevin Givens facing assault charge in Baltimore," 26 Mar. 2021 An arrest affidavit said Alissa bought a Ruger AR-556 pistol, which resembles an AR-15 rifle with a slightly shorter stock., "Colorado shooting suspect passed check in legal gun purchase," 26 Mar. 2021 The suspect, Ahmad Al Aliwi Alissa, purchased a semiautomatic pistol six days before Monday's shooting, according to his arrest warrant affidavit. Faith Karimi, CNN, "Colorado is one of four states whose laws don't prohibit someone with a mental illness from owning firearms," 25 Mar. 2021 Right now, voters who do not have photo identification can sign an affidavit attesting to their identity. Dave Boucher, Detroit Free Press, "Michigan GOP senators file 39 election reform bills Democrats call racist, based on lies," 25 Mar. 2021 While authorities have declined to absolutely link that footage to Alissa, an arrest affidavit described how the suspect surrendered to a SWAT team. NBC News, "Colorado shooting suspect to be held without bail, judge rules," 25 Mar. 2021 According to the affidavit released by police, Alissa lives on the top floor of a large two-story house. Washington Post, "Suspect in Boulder shooting had previously alarmed classmates with violent outbursts," 24 Mar. 2021 The arrest affidavit said that Alissa lived in suburban Arvada, just west of Denver. Los Angeles Times, "Suspect in Boulder mass shooting had a history of angry outbursts and an assault conviction," 23 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'affidavit.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of affidavit

1515, in the meaning defined above

History and Etymology for affidavit

borrowed from Medieval Latin affīdāvit "he/she has made a pledge," third person singular perfect indicative active of affīdāre — more at affiance entry 1

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Time Traveler for affidavit

Time Traveler

The first known use of affidavit was in 1515

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Statistics for affidavit

Last Updated

31 Mar 2021

Cite this Entry

“Affidavit.” Dictionary, Merriam-Webster, Accessed 10 Apr. 2021.

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More Definitions for affidavit



English Language Learners Definition of affidavit

law : a written report which is signed by a person who promises that the information is true


af·​fi·​da·​vit | \ ˌa-fə-ˈdā-vət How to pronounce affidavit (audio) \

Kids Definition of affidavit

: a written statement signed by a person who swears that the information is true


af·​fi·​da·​vit | \ ˌa-fə-ˈdā-vət How to pronounce affidavit (audio) \

Legal Definition of affidavit

: a sworn statement in writing made especially under oath or on affirmation before an authorized magistrate or officer — compare deposition, examination

History and Etymology for affidavit

Medieval Latin, he/she has pledged faith, third singular perfect of affidare — see affiant

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More from Merriam-Webster on affidavit

Nglish: Translation of affidavit for Spanish Speakers

Britannica English: Translation of affidavit for Arabic Speakers Encyclopedia article about affidavit

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