swear

US /swer/
UK /swer/
"swear" picture
1.

to use offensive language, especially as an expression of anger or frustration

:
He tends to swear a lot when he's angry.
Please don't swear in front of the children.
2.

to make a solemn promise, often by invoking a divine being or a sacred object

:
I swear to tell the truth, the whole truth, and nothing but the truth.
She made him swear on the Bible.
3.

to state or assert something very strongly and confidently

:
I could swear I saw him leave.
She would swear on her life that she was innocent.