頭を冷やせ

Cool off!

→ 頭
phrase Rare #32,481
Cool off! A forceful command telling someone to calm down and think more clearly. It is the imperative form of 頭を冷やす and can sound angry or confrontational. The softer form 頭を冷やして is more polite or less forceful.
JA: みんな、頭を冷やせ!
EN: Everyone, cool off!

頭を冷やせ

Cool your head.

みんな頭を冷やせ

Everyone, calm down.

— Carandiru (2003)

頭を冷やせ

Calm down.

— 人生スイッチ (2014)

頭を冷やせ

Cool your head!