剑出鞘

Traditional (Taiwan): 劍出鞘

jiànchūqiào ㄐㄧㄢˋ ㄔㄨ ㄑㄧㄠˋ

    • to be on high alert and ready for action

Character by character

Saying俗语俗語

Idiom惯用语 · Widely known

Literally
sword out of its sheath
Meaning
Being on high alert and ready for battle or action. Dramatic.

Sources