<recreation> (From the children's TV program "Sesame Street") Any of a family of early (1970s) hacks reported on TOPS-10, ITS, Multics and elsewhere that would lock up either the victim's terminal (on a time-sharing machine) or the console (on a batch mainframe), repeatedly demanding "I WANT A COOKIE". The required responses ranged in complexity from "COOKIE" through "HAVE A COOKIE" and upward.
See also wabbit.
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Nearby terms: cookie bear « cookie file « cookie jar « cookie monster » cooky » COOL » CooL