n. One that interferes with the affairs of others, often for selfish reasons; a meddler.n. One that intrudes in a place, situation, or activity: "When these interlopers choke out native species, ecologists see a danger signal” ( William K. Stevens). n. Archaic One that trespasses on a trade monopoly, as by conducting unauthorized trade in an area designated to a chartered company.n. Archaic A ship or other vessel used in such trade.