gatecrasher vs trespasser

gatecrasher and trespasser both are nouns.

Word	Noun	Adjective	Verb	Adverb
gatecrasher	Yes	No	No	No
trespasser	Yes	No	No	No

As nouns, trespasser is a hypernym of gatecrasher; that is, trespasser is a word with a broader meaning than gatecrasher:

gatecrasher: someone who gets in (to a party) without an invitation or without paying
trespasser: someone who intrudes on the privacy or property of another without permission

Other hypernyms of gatecrasher include interloper, intruder.

gatecrasher (noun)	trespasser (noun)
someone who gets in (to a party) without an invitation or without paying	someone who intrudes on the privacy or property of another without permission