A shout or whistle expressing dislike, especially from a crowd or audience; a jeer, a boo.
A whistle blown by a theatre-goer to express disapproval.
A shout, whistle, or comment of a sexual nature, usually made toward a passing woman.
In the Eiffel programming language, a run-time error caused by use of the wrong data type.
To make such an exclamation.
A hissing noise.
To make a hissing sound.