\ 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

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 Her critics argue that advanced age should not absolve her of having to pay the consequences for her actions — lying under oath, according to the book. Eugene Scott, Washington Post, "Why there’s little optimism after the Justice Department reopened the Emmett Till case," 12 July 2018 Attorneys for ExxonMobil want to question under oath the officials who signed off on their respective community’s lawsuits against energy companies, including Dedina and two others from Imperial Beach. Rob Nikolewski, sandiegouniontribune.com, "Imperial Beach pushes forward with lawsuit against oil companies," 27 June 2018 The poll also revealed that an overwhelming majority of Americans think Trump needs to testify under oath if Mueller calls for it. Li Zhou, Vox, "A new poll finds that 42 percent of Americans support the idea.," 22 June 2018 If the President refuses an interview with Mueller's office, prosecutors could then use a grand jury to subpoena him to testify under oath. Gloria Borger, CNN, "President Trump's legal team plots next move following the North Korea summit," 13 June 2018 Sessions straight up lied, under oath, about meeting with a Russian ambassador. Stephen A. Crockett Jr., The Root, "Trump Still Hates Jeff Sessions for Being Jeff Sessions," 30 May 2018 Home plate at Dunkin’ Donuts Park was briefly transformed into a federal courtroom on Wednesday as 50 people from 22 nations took the oath of allegiance and became United States citizens. David Owens, courant.com, "50 Immigrants From 22 Nations Become U.S. Citizens In A Ceremony Before The Fourth Of July Yard Goats Game," 4 July 2018 In a Facebook video, Enzo Russell can be seen taking the oath and being sworn in by the department chief. Lena Blietz, star-telegram, "A fallen officer's department honors him by "swearing in" his young nephew," 12 Feb. 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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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

10 Aug 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).


alleviating pain or harshness

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