Definition of "Gag" :

noun: restraint put into a person's mouth to prevent speaking or shouting

noun: a humorous anecdote or remark intended to provoke laughter

"He knows a million gags."

verb: make an unsuccessful effort to vomit; strain to vomit

verb: cause to retch or choke

verb: struggle for breath; have insufficient oxygen intake

"He swallowed a fishbone and gagged."

verb: make jokes or quips

"The students were gagging during dinner."

verb: tie a gag around someone's mouth in order to silence them

"The burglars gagged the home owner and tied him to a chair."

verb: be too tight; rub or press

verb: prevent from speaking out

"The press was gagged."