头脑发热

Traditional (Taiwan): 頭腦發熱

tóunǎofārè ㄊㄡˊ ㄋㄠˇ ㄈㄚ ㄖㄜˋ

    • to act on impulse without calm thought

Character by character

Saying俗语俗語

Idiom惯用语 · In everyday use

Literally
head running hot
Meaning
To act without calm thought, carried away by impulse. Mildly critical.

Sources