optical vs eye

optical is not a noun while eye is a noun.

Word	Noun	Adjective	Verb	Adverb
optical	No	Yes	No	No
eye	Yes	No	Yes	No

optical (noun)	eye (noun)
	a small hole or loop (as in a needle)
	the organ of sight
	good discernment (either visually or as if visually)
	attention to what is seen
	an area that is approximately central within some larger region

optical (adjective)	eye (adjective)
of or relating to or resembling the eye
of or relating to or involving light or optics
relating to or using sight

optical (verb)	eye (verb)
	look at