1. [n]  a form of life assumed to exist outside the Earth or its atmosphere
2. [n]  a person who comes from a foreign country; someone who does not owe allegiance to your country
3. [n]  anyone who does not belong in the environment in which they are found
4. [adj]  being or from or characteristic of another place or part of the world; "alien customs"; "exotic plants in a greenhouse"; "moved to a strange country"
5. [adj]  not contained in or deriving from the essential nature of something; "an economic theory alien to the spirit of capitalism"; "the mysticism so foreign to the French mind and temper"; "jealousy is foreign to her nature"
6. [v]  arouse hostility or indifference in where there had formerly been love, affection, or friendliness

1. \Al"ien\, a. [OF. alien, L. alienus, fr. alius another;
   properly, therefore, belonging to another. See {Else}.]
   1. Not belonging to the same country, land, or government, or
      to the citizens or subjects thereof; foreign; as, alien
      subjects, enemies, property, shores.
   2. Wholly different in nature; foreign; adverse; inconsistent
      (with); incongruous; -- followed by from or sometimes by
      to; as, principles alien from our religion.
            An alien sound of melancholy.         --Wordsworth.
   {Alien enemy} (Law), one who owes allegiance to a government
      at war with ours. --Abbott.
   

2. \Al"ien\, n.
   1. A foreigner; one owing allegiance, or belonging, to
      another country; a foreign-born resident of a country in
      which he does not possess the privileges of a citizen.
      Hence, a stranger. See {Alienage}.
   2. One excluded from certain privileges; one alienated or
      estranged; as, aliens from God's mercies.
            Aliens from the common wealth of Israel. --Ephes.
                                                  ii. 12.
   

3. \Al"ien\, v. t. [F. ali['e]ner, L. alienare.]
   To alienate; to estrange; to transfer, as property or
   ownership. [R.] ``It the son alien lands.'' --Sir M. Hale.
         The prince was totally aliened from all thoughts of . .
         . the marriage.                          --Clarendon.
   

a foreigner, or person born in another country, and therefore not entitled to the rights and privileges of the country where he resides. Among the Hebrews there were two classes of aliens.

(1.) Those who were strangers generally, and who owned no landed property.

(2.) Strangers dwelling in another country without being naturalized (Lev. 22:10; Ps. 39:12).

Both of these classes were to enjoy, under certain conditions, the same rights as other citizens (Lev. 19:33, 34; Deut. 10:19). They might be naturalized and permitted to enter into the congregation of the Lord by submitting to circumcision and abandoning idolatry (Deut. 23:3-8).

This term is used (Eph. 2:12) to denote persons who have no interest in Christ.