pharmacologist vs pill pusher

pharmacologist and pill pusher both are nouns.

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

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

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

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

pharmacologist (noun)	pill pusher (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