knock off vs quit

knock off and quit both are verbs.

Word	Noun	Adjective	Verb	Adverb
knock off	No	No	Yes	No
quit	No	No	Yes	No

As verbs, quit is a hypernym of knock off; that is, quit is a word with a broader meaning than knock off:

Other hypernyms of knock off include cease, discontinue, give up, lay off, stop.

knock off (verb)	quit (verb)
stop pursuing or acting	give up in the face of defeat of lacking hope; admit defeat
get rid of (someone who may be a threat) by killing	go away or leave
write quickly	turn away from; give up
take by theft	give up or retire from a position
cut the price of	put an end to a state or an activity