打幌子

dǎhuǎngzi ㄉㄚˇ ㄏㄨㄤˇ ˙ㄗ

    • to use a respectable name or pretext as cover for doing something unrelated

Character by character

Saying俗语俗語

Idiom惯用语 · In everyday use

Literally
hang out a shop sign
Meaning
To use some respectable name or pretext as a cover for doing something unrelated. Critical.

Sources