knock off 1. Informala. To take a break or rest from; stop: knocked off work at noon. b. To cease work: It's after five; let's knock off.
2. Informal To complete, accomplish, or dispose of hastily or easily; finish: That author knocks off a book a year. 3. Informal To get rid of; eliminate: knocked off 12 pounds in a month. 4. Slang To kill or overcome. 5. Slang To hold up or rob: knocked off a bank. 6. Informal To copy or imitate, especially without permission: knocking off someone else's ideas.