A kind of whistle used at theatres by the audience to express displeasure or impatience. A hideous noise like the call or waul of a cat.
“I was very much surprised with the great consort of cat-calls ... to see so many persons of quality of both sexes assembled together at a kind of caterwauling.” —Addison, Spectator, No. 361.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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