信号弹

Traditional (Taiwan): 信號彈

xìnhàodàn ㄒㄧㄣˋ ㄏㄠˋ ㄉㄢˋ

    • signal flare
    • something that conveys a message or hints at what is coming

Character by character

Saying俗语俗語

Idiom惯用语 · Widely known

Literally
signal flare
Meaning
Something that conveys a message or hints at what is coming.

Sources