reflectivity vs reflective

reflectivity is a noun but reflective is not a noun.

Word	Noun	Adjective	Verb	Adverb
reflectivity	Yes	No	No	No
reflective	No	Yes	No	No

reflectivity (noun)	reflective (noun)
the ability to reflect beams or rays
the capability of quiet thought or contemplation
the fraction of radiant energy that is reflected from a surface

reflectivity (adjective)	reflective (adjective)
	capable of physically reflecting light or sound
	devoted to matters of the mind
	deeply or seriously thoughtful