pare down vs decrease

pare down is not a noun while decrease is a noun.

Word	Noun	Adjective	Verb	Adverb
pare down	No	No	Yes	No
decrease	Yes	No	Yes	No

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

Other hypernyms of pare down include lessen, minify.

pare down (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

pare down (verb)	decrease (verb)
decrease gradually or bit by bit	decrease in size, extent, or range
	make become smaller