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.

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 Last week, Investigator Matt Haney of the Homer Police Department submitted an affidavit for an arrest warrant for Calderwood. Veronica Fulton, NBC News, 12 May 2022 On this October night, Coxey brought along an affidavit for a search warrant. Washington Post, 11 May 2022 But a 2014 search warrant affidavit from police in Connecticut pointed to Carman as the likely suspect. Globe Staff,, 11 May 2022 During that time, he was known to bring former students — all girls — to his class after school to visit, or help him with administrative paperwork, according to the probable cause affidavit in his arrest. Brooke Baitinger, Sun Sentinel, 11 May 2022 Investigators submitted a damning 50-page affidavit to support the arrest, claiming that electronic records, including Connie's Fitbit movements on the morning of her death, contradicted Dabate's account of her murder. Steve Helling,, 11 May 2022 On April 1, investigators obtained a warrant to get DNA from Jalonni Blackshear, according to Kleinsmith’s affidavit. Tess Williams, Anchorage Daily News, 10 May 2022 Video surveillance of the argument showed Gerald Randle pulled a revolver on the other man and hit him with it before both men fired at each other, each suffering head injuries, according to the probable cause affidavit in the case. oregonlive, 9 May 2022 But in a sign the task force may be unwilling in some cases to expose its tradecraft in tracking down assets, the 24-page affidavit presented to a federal judge in support of the seizure was heavily redacted. New York Times, 8 May 2022 See More

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.

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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Dictionary Entries Near affidavit



affidavit of merits

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Last Updated

18 May 2022

Cite this Entry

“Affidavit.” Dictionary, Merriam-Webster, Accessed 28 May. 2022.

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More Definitions for affidavit


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

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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