oath

American  

[ohth] / oʊθ /

noun

oaths plural

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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Other Word Forms

Noun Inflected Forms

• oaths
  plural

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

Technically, when Blanche promised lawmakers the anti-weaponization fund would not be moving forward, he was not under oath.

From Slate • Jun. 4, 2026

Noem has faced questioning before Congress about the alleged relationship, and attacked the reports as “tabloid garbage,” though she stopped short of explicitly denying the allegations while under oath.

From Salon • Jun. 4, 2026

He said Bondi, who was not under oath, declined to answer five questions he posed about the president.

From Los Angeles Times • May 29, 2026

Warsh is set to be sworn in as the nation’s top central banker at the White House on Friday, the first Fed chair to take the oath there since Alan Greenspan in 1987.

From The Wall Street Journal • May 22, 2026

A hand goes on a Bible; an oath gets repeated.

From "Becoming" by Michelle Obama

Related Words

• affidavit
• deposition
• pledge
• testimony
• vow