crap1 / krap/ vulgar slang • n. 1. something that is of extremely poor quality. ∎ nonsense. ∎ rubbish; junk.2. excrement. ∎ [in sing.] an act of defecation.• v. (crapped, crap·ping) [intr.] defecate.crap2 • n. a losing throw of 2, 3, or 12 in craps.• v. [intr.] (crap out) inf. make a losing throw at craps. ∎ withdraw from or give up on a game or activity because of fear or fatigue. ∎ fail in what one is attempting to do. ∎ (of a machine) break down.