Noun an imitation, especially one of poorer quality. This spreadsheet program is a knock off of Visicalc. Alternate spellings knock-off knockoff Verb to bump or hit so that something falls off My sleeve hit the vase and knocked it off the shelf. to quit; stop doing an activity I think I'll knock off for the evening and go to bed. to kill someone The mobsters hired the guy to knock off their enemies. Related terms bump off (3) knock knock down knock it off knock over knock one's socks off
