knock off vs steal

knock off is not a noun while steal is a noun.

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

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

Other hypernyms of knock off include rip, rip off.

knock off (noun)	steal (noun)
	a stolen base; an instance in which a base runner advances safely during the delivery of a pitch (without the help of a hit or walk or passed ball or wild pitch)
	an advantageous purchase

knock off (verb)	steal (verb)
stop pursuing or acting	steal a base
get rid of (someone who may be a threat) by killing	move stealthily
write quickly	take without the owner's consent
take by theft
cut the price of