oil color vs oil colour

oil color and oil colour both are nouns.

Word	Noun	Adjective	Verb	Adverb
oil color	Yes	No	No	No
oil colour	Yes	No	No	No

As nouns, oil color and oil colour are synonyms defined as:

oil color and oil colour: oil paint containing pigment that is used by an artist

Other synonyms of oil color include oil.

oil color (noun)	oil colour (noun)
oil paint containing pigment that is used by an artist	oil paint containing pigment that is used by an artist