antiquarian vs expert

antiquarian and expert both are nouns.

Word	Noun	Adjective	Verb	Adverb
antiquarian	Yes	Yes	No	No
expert	Yes	Yes	No	No

As nouns, expert is a hypernym of antiquarian; that is, expert is a word with a broader meaning than antiquarian:

antiquarian (noun)	expert (noun)
an expert or collector of antiquities	a person with special knowledge or ability who performs skillfully

antiquarian (adjective)	expert (adjective)
of or relating to antiques or antiquities	having or showing knowledge and skill and aptitude
of or relating to persons who study or deal in antiques or antiquities	of or relating to or requiring special knowledge to be understood