In flagrante delicto (Latin: "in blazing offence") or sometimes simply in flagrante (Latin: "in blazing") is a legal term used to indicate that a criminal has been caught in the act of committing an offence (compare corpus delicti). The colloquial "caught in the act", "caught with one's pants down" or "caught red-handed" are English equivalents.
The phrase combines the present active participle flagrāns (flaming or blazing) with the noun dēlictum (offence, misdeed, or crime). In this term the Latin preposition in, not indicating motion, takes the ablative. The closest literal translation would be "in blazing offence", where "blazing" is a metaphor for vigorous, highly visible action.
Aside from the legal meaning, the Latin term is often used colloquially as a euphemism for someone's being caught in the midst of sexual activity.