block off vs jam

block off is not a noun while jam is a noun.

Word	Noun	Adjective	Verb	Adverb
block off	No	No	Yes	No
jam	Yes	No	Yes	No

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

Other hypernyms of block off include block, close up, impede, obstruct, obturate, occlude.

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

Other hypernyms of block off include block, close up, impede, obstruct, obturate, occlude.

block off (noun)	jam (noun)
	deliberate radiation or reflection of electromagnetic energy for the purpose of disrupting enemy use of electronic devices or systems
	preserve of crushed fruit
	a dense crowd of people
	informal terms for a difficult situation

block off (verb)	jam (verb)
obstruct access to	interfere with or prevent the reception of signals
render unsuitable for passage	crowd or pack to capacity
block off the passage through	get stuck and immobilized
	block passage through
	crush or bruise
	press tightly together or cram
	push down forcibly