dark-gray vs oxford-gray

dark-gray and oxford-gray both are adjectives.

Word	Noun	Adjective	Verb	Adverb
dark-gray	No	Yes	No	No
oxford-gray	No	Yes	No	No

As adjectives, dark-gray and oxford-gray are synonyms defined as:

Other synonyms of dark-gray include dark-grey, oxford-grey.

dark-gray (adjective)	oxford-gray (adjective)
of a dark shade of grey	of a dark shade of grey