belittle vs decrease

belittle is not a noun while decrease is a noun.

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

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

Other hypernyms of belittle include lessen, minify.

belittle (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

belittle (verb)	decrease (verb)
lessen the authority, dignity, or reputation of	decrease in size, extent, or range
express a negative opinion of	make become smaller
cause to seem less serious; play down