stranger vs trespasser

stranger and trespasser both are nouns.

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

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

stranger: anyone who does not belong in the environment in which they are found
trespasser: someone who intrudes on the privacy or property of another without permission

Other hypernyms of stranger include interloper, intruder.

stranger (noun)	trespasser (noun)
anyone who does not belong in the environment in which they are found	someone who intrudes on the privacy or property of another without permission
an individual that one is not acquainted with