oil paint vs oil colour

oil paint and oil colour both are nouns.

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

As nouns, oil colour is a hyponym of oil paint; that is, oil colour is a word with a more specific, narrower meaning than oil paint:

Other hyponyms of oil paint include oil, oil color.

oil paint (noun)	oil colour (noun)
paint in which a drying oil is the vehicle	oil paint containing pigment that is used by an artist