pharmacologist vs pill roller

pharmacologist and pill roller both are nouns.

Word	Noun	Adjective	Verb	Adverb
pharmacologist	Yes	No	No	No
pill roller	Yes	No	No	No

As nouns, pill roller is a hypernym of pharmacologist; that is, pill roller is a word with a broader meaning than pharmacologist:

pharmacologist: someone trained in the science of drugs (their composition and uses and effects)
pill roller: a health professional trained in the art of preparing and dispensing drugs

Other hypernyms of pharmacologist include apothecary, chemist, druggist, pharmacist, pill pusher.

pharmacologist (noun)	pill roller (noun)
someone trained in the science of drugs (their composition and uses and effects)	a health professional trained in the art of preparing and dispensing drugs