Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “swear”

See all translations

swear

verb uk   /sweər/ us    /swer/ (swore, sworn)

swear verb (USE RUDE WORDS)

B2 [I] to use words that are rude or offensive as a way of emphasizing what you mean or as a way of insulting someone or something: It was a real shock, the first time I heard my mother swear. When the taxi driver started to swear at him, he walked off.
More examples

swear verb (PROMISE)

B2 [I or T] to promise or say firmly that you are telling the truth or that you will do something or behave in a particular way: I don't know anything about what happened, I swear (it). [+ (that)] You might find it difficult to believe, but I swear (that) the guy just came up to me and gave me the money. informal She swore blind (= promised definitely) (that) she didn't know what had happened to the money. [+ to infinitive] New gang members must swear to obey the gang leaders at all times. In some countries, witnesses in court have to swear on the Bible. I swore an oath to tell the truth, the whole truth, and nothing but the truth. A few of us knew what was going to happen, but we were sworn to secrecy (= we were made to promise to keep it a secret). I think his birthday is on the 5th, but I wouldn't/couldn't swear to it (= I am not completely certain about it).
More examples
  • He swore he would avenge his brother's death.
  • He swore he'd pay her back for all she'd done to him.
  • Soldiers must swear allegiance to the Crown.
  • I swear to God I didn't know about it.
  • I want you to swear that you will never try to see her again.
(Definition of swear from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of swear?
Add Cambridge dictionaries to your browser to your website

Definitions of “swear” in other dictionaries

Word of the Day

pup

a baby of particular animals, or a puppy

Word of the Day

I won’t tolerate it! Replacing formal words with phrasal verbs.

by Liz Walter,
April 01, 2015
When you are using a language, it is important to understand if a word is formal or informal, so that you can use it in an appropriate way. You might hear people saying dosh for money, or spud for potato, but they wouldn’t write those words in a formal essay. Similarly, a

Read More 

stackin’ p

March 30, 2015
idiom slang earning a lot of money ‘That’s a very generous present.”Yeah, well, she’s stackin’ p, innit?’

Read More