int., n., & v.
int. 1 an expression of disapproval or contempt. 2 a sound, made esp. to a child, intended to surprise.
n. an utterance of boo, esp. as an expression of disapproval or contempt made to a performer etc.
v. (boos, booed) 1 intr. utter a boo or boos. 2 tr. jeer at (a performer etc.) by booing. can't (or wouldn't) say boo to a goose is very shy or timid.
[ imit. ]