chrome green vs viridity

chrome green and viridity both are nouns.

Word	Noun	Adjective	Verb	Adverb
chrome green	Yes	No	No	No
viridity	Yes	No	No	No

As nouns, viridity is a hypernym of chrome green; that is, viridity is a word with a broader meaning than chrome green:

Other hypernyms of chrome green include green, greenness.

chrome green (noun)	viridity (noun)
a brilliant green color	green color or pigment; resembling the color of growing grass
any of a class of green pigments consisting of chrome yellow and iron blue