Knock off is a commonly used phrasal verb in English, which means to stop working or doing something, or to make something quickly. There are many synonyms for this phrasal verb, such as cease, desist, terminate, halt, discontinue, quit, end, and suspend. Each of these synonyms conveys a slightly different meaning, but they are all alternatives to using the phrase "knock off." For instance, "cease" and "desist" mean to stop doing something and "terminate," "halt," and "suspend" indicate a more permanent stoppage. "Quit" and "discontinue" imply a personal decision to stop doing something. All of these synonyms can be used interchangeably to add variety and clarity to your writing or speech.