a·li·en

a·li·en (l-n, lyn)
adj.

1. Owing political allegiance to another country or government; foreign: alien residents.
2. Belonging to, characteristic of, or constituting another and very different place, society, or person; strange.
   
3. Dissimilar, inconsistent, or opposed, as in nature: emotions alien to her temperament.

n.

1. An unnaturalized foreign resident of a country. Also called noncitizen.
2. A person from another and very different family, people, or place.
3. A person who is not included in a group; an outsider.
4. A creature from outer space: science fiction about an invasion of aliens.
5. Ecology. An organism, especially a plant or animal, that occurs in or is naturalized in a region to which it is not native.