oath

American  

[ohth] / oʊθ /

noun

plural

oaths

1. a solemn appeal to a deity, or to some revered person or thing, to witness one's determination to speak the truth, to keep a promise, etc..

   to testify upon oath.

2. a statement or promise strengthened by such an appeal.

   Synonyms:

   pledge, vow

3. a formally affirmed statement or promise accepted as an equivalent of an appeal to a deity or to a revered person or thing; affirmation.

4. the form of words in which such a statement or promise is made.

5. an irreverent or blasphemous use of the name of God or anything sacred.

   Synonyms:

   profanity

6. any profane expression; curse; swear word.

   He slammed the door with a muttered oath.

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idioms

1. take an oath, to swear solemnly; vow.

oath British  

/ əʊθ /

noun

1. a solemn pronouncement to affirm the truth of a statement or to pledge a person to some course of action, often involving a sacred being or object as witness

2. the form of such a pronouncement

3. an irreverent or blasphemous expression, esp one involving the name of a deity; curse

4. 1. under the obligation of an oath

   2. law having sworn to tell the truth, usually with one's hand on the Bible

5. to declare formally with an oath or pledge, esp before giving evidence

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Etymology

Origin of oath

First recorded before 900; Middle English oth, Old English āth; cognate with Gothic aiths, Old Norse eidhr, German Eid

Explanation

An oath is a promise. If you want to borrow your brother's car, you may have to swear a solemn oath that you will bring it back unharmed. An oath is a solemn promise, sometimes made in front of a witness, or a vow in a court of law that you will tell the absolute truth. No matter what the circumstances are, swearing an oath is serious business. That's why it's odd that an oath can also be an angry outburst of obscene words. Your brother might mutter an oath under his breath and clench his fists angrily if you return his car to him with a broken side mirror.

Example Sentences

For Blood Oath, it started when I was at my birthday party in 2024 with a small group of friends.

From Los Angeles Times • Apr. 21, 2026

Oath Keepers founder Stewart Rhodes was originally sentenced to 18 years in prison.

From Salon • Apr. 15, 2026

Those are the first words of the military Oath of Enlistment—the words that new members of the military, with right hands raised, intone as they join the service.

From The Wall Street Journal • Mar. 29, 2026

Healthcare costs were the top financial concern for retirement investors in 2026, according to an Oath Money & Meaning Institute survey released this month.

From MarketWatch • Jan. 30, 2026

‘You smell -’ ‘I know. Like I’ve been dead. Probably because I have been. Oath to keep with a final breath and all, but I’m better now -’ She stopped him with a kiss.

From "Blood of Olympus" by Rick Riordan

Related Words

• affidavit
• deposition
• pledge
• testimony
• vow