#intruder__interloper__trespasser  someone who intrudes on the privacy or property of another without permission
  supertype:  entrant.traveler  unwelcome_person
  subtype:  boarder.intruder  someone who forces their way aboard ship; "stand by to repel boarders"
  subtype:  gatecrasher__unwelcome_guest  someone who gets in (to a party) without an invitation or without paying
  subtype:  infiltrator  an intruder (as troops) with hostile intent
  subtype:  invader__encroacher  someone who enters by force in order to conquer
  subtype:  penetrator  an intruder who passes into or through (often by overcoming resistance)
  subtype:  prowler__sneak__stalker  someone who prowls or sneaks about; usually with unlawful intentions
  subtype:  pusher__thruster  one who intrudes or pushes himself forward
  subtype:  squatter  someone who settles on land without right or title
  subtype:  stranger__alien__unknown  anyone who does not belong in the environment in which they are found
     subtype:  foreigner__outsider  someone who is not a member of a group
        subtype:  transalpine  one living on or coming from the other side of the Alps from Italy

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