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

Blood taken at Parkland Memorial Hospital showed a preliminary blood-alcohol content of .143, well over the state's legal driving limit, according to an arrest-warrant affidavit issued for Arenas. Loyd Brumfield, Dallas News, "DWI suspect in Camaro hit 83 mph just before deadly pileup in northwest Dallas," 2 July 2019 According to the affidavit of probable cause, Graham changed his statement after he was arrested for an unrelated robbery. Steve Helling,, "N.J. Man Claimed His Girlfriend’s Daughter Fell Down Stairs, But Now Admits to Killing Her," 1 July 2019 The guests told the inspectors that their Airbnb host was a man named Bloz, according to an affidavit from an inspector. Paris Martineau, WIRED, "How 9 People Built an Illegal $5M Airbnb Empire in New York," 24 June 2019 The sailor had a combination of narcotics in his system, including levels of fentanyl that the Medical Examiner’s Office opined were within ranges associated with toxic effects and death, according to an affidavit seeking a warrant to arrest Martin. San Diego Union-Tribune, "Drug rehab counselor charged with murder in Navy man’s fentanyl overdose death," 22 June 2019 According to an affidavit, a deputy responded to their home on North Maine Avenue about 11 a.m. April 29, arriving to find Randy Haynes lying on the ground with blood pooling under his head. Jeff Weiner,, "Death of man injured in fight with brother near Apopka deemed homicide by medical examiner," 21 June 2019 During one exam, according to an affidavit, an undercover agent asked why a nurse practitioner was inspecting his arms. Del Quentin Wilber,, "12 million pills and 700 deaths: How a few pill mills helped fan the U.S. opioid inferno," 14 June 2019 The Ohio Innocence Project and other attorneys helped persuade county judges in Cleveland to exonerate the men after obtaining an affidavit from a man named Eddie Vernon in 2013. Mark Gillispie, The Seattle Times, "Appeals court says exonerated men’s claims should be heard," 29 Mar. 2019 In a 4-minute clip posted on Sunday (July 8), Jake Gyllenhaal, Ryan Reynolds and Lena Waithe among others read an affidavit from a migrant mother from Honduras named Mirian, who was separated from her 18-month-old son at the Texas border. Rania Aniftos, Billboard, "Jake Gyllenhaal, Ryan Reynolds & More Read Heart Wrenching Letter From Migrant Mother," 10 July 2018

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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Statistics for affidavit

Last Updated

9 Jul 2019

Look-up Popularity

Time Traveler for affidavit

The first known use of affidavit was in 1515

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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

Spanish Central: Translation of affidavit

Nglish: Translation of affidavit for Spanish Speakers

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

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