The history of theater is not always pretty, as evidenced by the arrival in the 16th century of the derisive whistle known as a cat call. Audience members who wanted to express their displeasure at a specific actor would often launch into a loud and jeering whistle said to resemble the plaintive wail of a cat. This noise could be heard onstage, much to the chagrin of the targeted performer or playwright. Instead of a receptive curtain call, a number of actors received a cat call at the end of an unpopular performance.
The cat call remained part of an unreceptive audience's arsenal for centuries. Modern audiences have largely abandoned the practice, but an occasional jeer or Bronx cheer may still be heard whenever a performer fails to win over the crowd or deliberately insults his or her audience. Hecklers at a comedy show, for example, may still issue a piercing call whenever a comedian's material fails.
A cat call is often paired in people's minds with the wolf whistle, a two-toned whistling noise usually directed at attractive members of the opposite sex. A cat call may be a series of loud cries used as an attention getter, while the salacious wolf whistle essentially seals the deal. The noise isn't always meant to be derisive, but it is meant to be noticed. Whoops, hollers, Bronx cheers and other rude noises could all fall under this term.
The expression can be a little confusing, since most cat owners will attest that calling an actual cat is nearly impossible. It is more likely that the term came from "caterwauling, the incredible amount of noise generated by cats who congregate in alleys at night. The sound is unmistakably harsh, much like the loud jeers and whistles created during a audience's cat call.