intruder vs pusher

intruder and pusher both are nouns.

Word	Noun	Adjective	Verb	Adverb
intruder	Yes	No	No	No
pusher	Yes	No	No	No

As nouns, pusher is a hyponym of intruder; that is, pusher is a word with a more specific, narrower meaning than intruder:

intruder: someone who intrudes on the privacy or property of another without permission
pusher: one who intrudes or pushes himself forward

intruder (noun)	pusher (noun)
someone who intrudes on the privacy or property of another without permission	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