drug dealer vs pusher

drug dealer and pusher both are nouns.

Word	Noun	Adjective	Verb	Adverb
drug dealer	Yes	No	No	No
pusher	Yes	No	No	No

As nouns, drug dealer and pusher are synonyms defined as:

Other synonyms of drug dealer include drug peddler, drug trafficker, peddler.

drug dealer (noun)	pusher (noun)
an unlicensed dealer in illegal drugs	a small vehicle with four wheels in which a baby or child is pushed around
	a sandal attached to the foot by a thong over the toes
	someone who pushes
	an unlicensed dealer in illegal drugs
	one who intrudes or pushes himself forward