crystallographer vs specialist

crystallographer and specialist both are nouns.

Word	Noun	Adjective	Verb	Adverb
crystallographer	Yes	No	No	No
specialist	Yes	No	No	No

As nouns, specialist is a hypernym of crystallographer; that is, specialist is a word with a broader meaning than crystallographer:

crystallographer: a specialist in crystallography
specialist: an expert who is devoted to one occupation or branch of learning

Other hypernyms of crystallographer include specialiser, specializer.

crystallographer (noun)	specialist (noun)
a specialist in crystallography	an expert who is devoted to one occupation or branch of learning
	practices one branch of medicine