chromatic color vs spectral colour

chromatic color and spectral colour both are nouns.

Word	Noun	Adjective	Verb	Adverb
chromatic color	Yes	No	No	No
spectral colour	Yes	No	No	No

As nouns, chromatic color and spectral colour are synonyms defined as:

Other synonyms of chromatic color include chromatic colour, spectral color.

chromatic color (noun)	spectral colour (noun)
a color that has hue	a color that has hue