colobus vs colobus monkey

colobus and colobus monkey both are nouns.

Word	Noun	Adjective	Verb	Adverb
colobus	Yes	No	No	No
colobus monkey	Yes	No	No	No

As nouns, colobus and colobus monkey are synonyms defined as:

colobus and colobus monkey: arboreal monkey of western and central Africa with long silky fur and reduced thumbs

colobus (noun)	colobus monkey (noun)
arboreal monkey of western and central Africa with long silky fur and reduced thumbs	arboreal monkey of western and central Africa with long silky fur and reduced thumbs