differ vs contrast

differ is not a noun while contrast is a noun.

Word	Noun	Adjective	Verb	Adverb
differ	No	No	Yes	No
contrast	Yes	No	Yes	No

As verbs, contrast is a hyponym of differ; that is, contrast is a word with a more specific, narrower meaning than differ:

Other hyponyms of differ include depart, deviate, diverge, vary, vary, counterpoint.

differ (noun)	contrast (noun)
	the act of distinguishing by comparing differences
	the range of optical density and tone on a photographic negative or print (or the extent to which adjacent areas on a television screen differ in brightness)
	the perceptual effect of the juxtaposition of very different colors
	a conceptual separation or distinction
	the opposition or dissimilarity of things that are compared

differ (verb)	contrast (verb)
be of different opinions	put in opposition to show or emphasize differences
be different	to show differences when compared; be different