扯大旗

chědàqí ㄔㄜˇ ㄉㄚˋ ㄑㄧˊ

    • to rally people under a banner
    • to borrow authority by invoking a name

Character by character

Saying俗语俗語

Idiom惯用语 · Widely known

Literally
to pull out a big flag
Meaning
To openly rally people under some banner or name, sometimes to borrow authority. Can be critical.

Sources