"Empowering Advanced Learners of English in Business and Academia - TOEFL / ESL / EFL"
Definition
This expression is used to tell someone to calm down.
Context : Relationships, Social Life
Category: Idiom
Semantic: calm down
Usage of “keep your shirt on”
Keep your shirt on! You only won a little bit of money, it's not that big of a deal.
Examples of idiom “keep your shirt on” from Twitter