stop vs block off

stop is a noun but block off is not a noun.

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

As verbs, stop and block off are synonyms defined as:

Other synonyms of stop include bar, barricade, block, block up, blockade.

As verbs, block off is a hyponym of stop; that is, block off is a word with a more specific, narrower meaning than stop:

Other hyponyms of stop include close off, shut off, close.

stop (noun)	block off (noun)
the act of stopping something
a brief stay in the course of a journey
a restraint that checks the motion of something
an obstruction in a pipe or tube
a mechanical device in a camera that controls size of aperture of the lens
(music) a knob on an organ that is pulled to change the sound quality from the organ pipes
a consonant produced by stopping the flow of air at some point and suddenly releasing it
a punctuation mark (.) placed at the end of a declarative sentence to indicate a full stop or after abbreviations
the event of something ending
a spot where something halts or pauses
the state of inactivity following an interruption

stop (verb)	block off (verb)
prevent completion	obstruct access to
stop and wait, as if awaiting further instructions or developments	render unsuitable for passage
hold back, as of a danger or an enemy; check the expansion or influence of	block off the passage through
seize on its way
render unsuitable for passage
come to a halt, stop moving
cause to end
interrupt a trip
stop from happening or developing
put an end to a state or an activity
have an end, in a temporal, spatial, or quantitative sense; either spatial or metaphorical