taper off vs narrow

taper off is not a noun while narrow is a noun.

Word	Noun	Adjective	Verb	Adverb
taper off	No	No	Yes	No
narrow	Yes	Yes	Yes	No

As verbs, narrow is a hypernym of taper off; that is, narrow is a word with a broader meaning than taper off:

Other hypernyms of taper off include contract.

taper off (noun)	narrow (noun)
	a narrow strait connecting two bodies of water

taper off (adjective)	narrow (adjective)
	not wide
	very limited in degree
	lacking tolerance or flexibility or breadth of view
	characterized by painstaking care and detailed examination
	limited in extent or scope

taper off (verb)	narrow (verb)
become smaller or less active	make or become more narrow or restricted
end weakly	become tight or as if tight
	become more focused on an area of activity or field of study
	define clearly