A side, party (e.g. a team or armed force) seen as adversary, enemy etc. opposite one (or more) other(s), as in a battle or team sports competition.
One not privy or party to an act, contract, or title; a mere intruder or intermeddler; one who interferes without right.
One who has not been seen for a long time.
A person whom one does not know; a person who is neither a friend nor an acquaintance.
A newcomer.
An outsider or foreigner.
One not admitted to communion or fellowship.