disappear vs pass off

disappear and pass off both are verbs.

Word	Noun	Adjective	Verb	Adverb
disappear	No	No	Yes	No
pass off	No	No	Yes	No

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

disappear (verb)	pass off (verb)
get lost, as without warning or explanation	expel (gases or odors)
cease to exist	come to pass
become less intense and fade away gradually	disappear gradually
become invisible or unnoticeable	disregard
	cause to be circulated and accepted in a false character or identity
	be accepted as something or somebody in a false character or identity