\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

But unless the new allegations are false — which would mean Pinheiro would be lying under oath — some of the most vulnerable asylum seekers are in fact being turned away. Dara Lind, Vox, "Mexico won’t let kids go to a US port. Trump doesn’t want to give them other options.," 21 Nov. 2018 Answer: Hiram paid Cassidy’s three friends $10,000 each to lie under oath. Jessica Macleish, Teen Vogue, ""Riverdale" Recap Season 3 Episode 5: Can Archie Escape From a Teenage Fight Club?!," 15 Nov. 2018 Democratic Senators are already calling for Kavanaugh’s nomination to be withdrawn before Dr. Ford even takes the stand: There are three women willing to testify under oath about credible allegations. Cady Drell, Marie Claire, "Christine Blasey Ford's Testimony—Here's Everything You Should Know," 26 Sep. 2018 In case after case, Guevara has repeatedly refused to testify when asked under oath about allegations of wrongdoing. Jason Meisner, chicagotribune.com, "Federal jury finds Chicago police framed man for 1988 murder, awards him more than $17 million," 29 June 2018 As part of the accord, American agreed to produce business records and make as many as three current or former employees available to answer questions under oath about its documents and transactional data. Fortune, "American Airlines to Pay $45 Million to End Consumer Antitrust Lawsuit," 16 June 2018 On another day, Punk testified under oath about the origins of his ring name. Justin Barrasso, SI.com, "For CM Punk, Defamation Trial Proved to Be a Blessing in Disguise for UFC 225 Training," 7 June 2018 Spielman gave a statement under oath about his participation in the alleged hazing incident that prosecutors said could be used in the trials of the other players. Clifford Ward, Wheaton Glen Ellyn, "July trial set for former Wheaton College football player accused with others of injuring teammate during hazing," 3 May 2018 The civil lawsuit could force President Donald Trump’s 2016 staffers to answer questions under oath about campaign activities. Bloomberg.com, "DNC Sues Trump Campaign, WikiLeaks, Russia Over Election Interference," 20 Apr. 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

Statistics for oath

Last Updated

30 Nov 2018

Look-up Popularity

Time Traveler for oath

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

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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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More from Merriam-Webster on oath

Rhyming Dictionary: Words that rhyme with oath

Thesaurus: All synonyms and antonyms for oath

Spanish Central: Translation of oath

Nglish: Translation of oath for Spanish Speakers

Britannica English: Translation of oath for Arabic Speakers

Britannica.com: Encyclopedia article about oath

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).


to enclose within walls

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