\ˈōth \
plural oaths\ˈōt͟hz, ˈōths \

Definition of oath 

1a(1) : a solemn usually formal calling upon God or a god to witness to the truth of what one says or to witness that one sincerely intends to do what one says

(2) : a solemn attestation of the truth or inviolability of one's words The witness took an oath to tell the truth in court.

b : something (such as a promise) corroborated by an oath They were required to swear an oath of loyalty. took the oath of office

2 : an irreverent or careless use of a sacred name broadly : swear word He uttered an oath and stormed away.

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Synonyms for oath


pledge, promise, troth, vow, word

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Examples of oath in a Sentence

an oath to defend the nation He uttered an oath and walked away.

Recent Examples on the Web

New Supreme Court Justice Neil Gorsuch shakes President Donald Trump's hand after taking the judicial oath at the White House on April 10, 2017. Jeffrey Rosen, WSJ, "What We Learn from Supreme Court Confirmation Hearings," 13 July 2018 Residents can also give feedback under oath at the administrative law judge hearing. Libby Solomon, baltimoresun.com, "Widespread support, a couple passionate detractors at Bosley Estates public meeting," 12 July 2018 In the complaint filed in Leon County court in Tallahassee, Eskamani claims Forges’s wife, Patricia Forges, signed and notarized his filing paperwork, including his candidate oath and his disclosure form. Steven Lemongello, OrlandoSentinel.com, "Anna Eskamani sues primary opponent, calls his candidacy 'fake'," 6 July 2018 In a typical swearing-in ceremony, the oath of office will be administered to two or three new hires or officers moving up in rank, Naperville Police Chief Robert Marshall said. Rafael Guerrero, Naperville Sun, "Naperville police swear in new commanders, sergeants and officers to fill ranks after flood of retirements," 22 June 2018 For two officers in Roanoke, Virginia, the oath of protecting and serving their community extended to a snake that needed help crossing a street. Christopher Brito, CBS News, "Police officers halt traffic to help snake cross busy Virginia street," 19 June 2018 The court upheld a June 2016 ruling that two Merck patents, which cover methods of treating hepatitis C, were unenforceable because of a pattern of misconduct by the company, including lying under oath by an in-house lawyer. Ed Silverman, STAT, "Pharmalittle: FDA probes safety of Parkinson’s drug; Koch brothers push new ‘right to try’ ads," 26 Apr. 2018 Haston said the colonel who administered the oath was immediately retired at the rank of Lieutenant General. Leada Gore, AL.com, "Air National Guard members punished over dinosaur video," 19 Apr. 2018 The first time a nominee testified under oath in fully public hearings was in 1939, when Felix Frankfurter appeared before the Senate to answer charges of disloyalty for his civil libertarian sympathies. Jeffrey Rosen, WSJ, "What We Learn from Supreme Court Confirmation Hearings," 13 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'oath.' 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 oath

before the 12th century, in the meaning defined at sense 1a(1)

History and Etymology for oath

Middle English ooth, from Old English āth; akin to Old High German eid oath, Middle Irish oeth

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Learn More about oath

Dictionary Entries near oath



oat grass



oath helper

oath of calumny

Phrases Related to oath

oath of office

on oath

under oath

Statistics for oath

Last Updated

21 Sep 2018

Look-up Popularity

Time Traveler for oath

The first known use of oath was before the 12th century

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More Definitions for oath



English Language Learners Definition of oath

: a formal and serious promise to tell the truth or to do something

: an offensive or rude word that is used to express anger, frustration, surprise, etc.


\ˈōth \
plural oaths\ˈōt͟hz, ˈōths \

Kids Definition of oath

1 : a solemn promise to tell the truth or do a specific thing

2 : an obscene or impolite word used to express anger or frustration


Medical Definition of oath 

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Legal Definition of oath 

1 : a solemn attestation of the truth of one's words or the sincerity of one's intentions specifically : one accompanied by calling upon a deity as a witness

2 : a promise (as to perform official duties faithfully) corroborated by an oath — compare perjury

under oath

: under a solemn and especially legal obligation to tell the truth (as when testifying)

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Comments on oath

What made you want to look up oath? Please tell us where you read or heard it (including the quote, if possible).


not any or not one

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