vanish vs decrease

vanish is not a noun while decrease is a noun.

Word	Noun	Adjective	Verb	Adverb
vanish	No	No	Yes	No
decrease	Yes	No	Yes	No

As verbs, decrease is a hypernym of vanish; that is, decrease is a word with a broader meaning than vanish:

Other hypernyms of vanish include diminish, fall, lessen.

vanish (noun)	decrease (noun)
	the act of decreasing or reducing something
	the amount by which something decreases
	a change downward
	a process of becoming smaller or shorter

vanish (verb)	decrease (verb)
get lost, as without warning or explanation	decrease in size, extent, or range
decrease rapidly and disappear	make become smaller
cease to exist
pass away rapidly
become invisible or unnoticeable