hush (one's) mouth
To stop talking; be quiet; shut up. Typically used as an imperative. Would you hush your mouth already? I'm sick of hearing you complain. The professor told the class to hush their mouths before he began his lecture.
Hush your mouth!
Inf Please be quiet. (Not very polite.) I've heard enough of that talk. Hush your mouth! Now, hush your mouth! You shouldn't talk like that!