arriviste, buttinsky, caller, company, crasher, emigrant, encroacher, freeloader, frequenter, greenhorn, guest, habitue, immigrant, infiltrator, interloper, intruder, invader, moocher, new arrival, new boy, newcomer, novus homo, parvenu, recruit, rookie, settler, squatter, stowaway, tenderfoot, trespasser, uninvited guest, unwelcome guest, upstart, visitant, visitor