keep your hair on
US /kiːp jʊər hɛər ɒn/
UK /kiːp jʊər hɛər ɒn/

1.
冷静, 别激动
used to tell someone to calm down and not get angry or upset
:
•
Just keep your hair on, there's no need to get so worked up.
冷静点,没必要这么激动。
•
Hey, keep your hair on! It was just a joke.
嘿,别激动!那只是个玩笑。