ALL meanings of belt up
belt up
B b - phrasal verb belt up If someone tells you to belt up, they are telling you in a very impolite way to stop talking. 3
- verb belt up to become or cause to become silent; stop talking: often used in the imperative 3
- verb belt up to fasten with or by a belt, esp a seat belt 3
- intransitivephrasal verb belt up fasten seatbelt 1
- intransitivephrasal verb belt up stop talking 1