keep your shirt on
US /kiːp jʊər ʃɜːrt ɑːn/
UK /kiːp jʊər ʃɜːrt ɑːn/

1.
se calmer, ne pas s'énerver
to tell someone to calm down or not to get angry
:
•
Just keep your shirt on, we'll get there eventually.
Calme-toi, on y arrivera finalement.
•
Hey, keep your shirt on! There's no need to yell.
Hé, calme-toi ! Pas besoin de crier.