{v. phr.}, {slang} To stop talking; keep a secret; shut your mouth; be quiet. * /The man was getting loud and insulting and the cop told him to button his lip./ * /John wanted to talk, but Dan told him to keep his lip buttoned./ Syn.: KEEP ONE'S MOUTH SHUT, SHUT UP.
ZIP ONE'S LIP
Meaning of ZIP ONE'S LIP in English
Slang English vocab. Английский сленговый словарь. 2012