Perjury (noun)

The voluntary violation of an oath or vow either by swearing to what is untrue or by omission to do what has been promised under oath.

Origin:

Middle english perjurie, from old french parjurie, from latin periuria, from per- thoroughly + ius right, law.

Examples:

1. He was charged with perjury for lying under oath.
2. The witness' testimony was deemed as perjury and she was charged.
3. The lawyer accused the witness of perjury.
4. Perjury is a serious offence and can lead to imprisonment.
5. The court found him guilty of perjury for making false statements under oath.