Synonyms of the word 
TRESPASSER → ENTRANT - INTERLOPER - INTRUDER
trespasser
- n. One who trespasses; an interloper.
entrant
- n. A participant who enters something, such as a contest.
- n. A newcomer.
interloper
- n. (obsolete) An unlicensed or illegitimate trader.
- n. One who interferes, intrudes or gets involved where not welcome, particularly a self-interested intruder.
intruder
- n. Someone who intrudes.
If you are interested in words, visit the following sites :
- wiktionary.org/trespasser For complete definition of a word
- 1word.ws/trespasser to play with words, suffixs, prefixs, etc.