亮牌子

liàngpáizi ㄌㄧㄤˋ ㄆㄞˊ ˙ㄗ

    • to reveal one's identity or position
    • to state one's views openly

Character by character

Saying俗语俗語

Idiom惯用语 · Widely known

Literally
show one's sign
Meaning
Either to reveal one's identity or position, or to state one's views openly.

Sources