arrival, arriviste, black sheep, blemish, burglar, busybody, buttinsky, comer, crasher, emigrant, encroacher, entrant, foreign body, foreign intruder
, gate-crasher, gatecrasher, greenhorn, immigrant, impurity, in-migrant, incomer, infiltrator, interloper, invader, kibitzer, meddler, misfit, monkey wrench, mote, new arrival, new boy, newcomer, novus homo, oddball, parvenu, recruit, rookie, settler, sliver, snooper, speck, splinter, squatter, stone, stowaway, tenderfoot, thief, trespasser, uninvited guest, unwelcome guest, upstart, visitant, visitor, weed
extraneousness, extrinsicality, exteriority, alienage, alienism, foreign body, foreign substance, foreign element, alien, stranger, intruder
, interloper, foreigner, novus homo, newcomer, immigrant, emigrant, creole, Africander, outsider, Dago, wop, mick, polak, greaser, slant, Easterner, Dutchman, tenderfoot, extraneous, foreign, alien, ulterior, tramontane, ultramontane, excluded, inadmissible, exceptional, in foreign parts, in foreign lands, abroad, beyond seas, over sea on one's travels.
interposition, interjacence, intercurrence, intervenience, interlocation, interdigitation, interjection, interpolation, interlineation, interspersion, intercalation, interpenetration, permeation, infiltration, intervention, interference, intrusion, obtrusion, insinuation, insertion, dovetailing, embolism, intermediary, intermedium, go between, bodkin, intruder
, interloper, parenthesis, episode, flyleaf, partition, septum, diaphragm, midriff, dissepiment, party wall, panel, room divider, halfway house, interjacent, intercurrent, intervenient, intervening, intermediate, intermediary, intercalary, interstitial, embolismal, parenthetical, episodic, mediterranean, intrusive, embosomed, merged, between, betwixt, twixt, among, amongst, amid, amidst, mid, midst, in the thick of, betwixt and between, sandwich-wise, parenthetically, obiter dictum.