photochromic eyewear vs shades

photochromic eyewear and shades both are nouns.

Word	Noun	Adjective	Verb	Adverb
photochromic eyewear	Yes	No	No	No
shades	Yes	No	No	No

As nouns, shades is a hypernym of photochromic eyewear; that is, shades is a word with a broader meaning than photochromic eyewear:

photochromic eyewear: Any eyeglasses with photochromic lenses with darken when exposed to sunlight.
shades: (plural) spectacles that are darkened or polarized to protect the eyes from the glare of the sun

Other hypernyms of photochromic eyewear include dark glasses, sunglasses.

photochromic eyewear (noun)	shades (noun)
Any eyeglasses with photochromic lenses with darken when exposed to sunlight.	(plural) spectacles that are darkened or polarized to protect the eyes from the glare of the sun
	(plural) something that reminds you of someone or something