Definition of "alien" in English

noun

1. A person, animal, plant, or other thing which is from outside the family, group, organization, or territory under consideration.

2. A citizen or national of another sovereign state.

3. (sometimes derogatory) A mischievous or suspicious foreigner.

4. Any life form of extraterrestrial or extradimensional origin.

5. One excluded from certain privileges; one alienated or estranged.

adjective

1. Not belonging to the same country, land, or government, or to the citizens or subjects thereof; foreign.

   • alien subjects, enemies, property, or shores

2. Very unfamiliar, strange, or removed.

   • principles alien to our religion

3. Pertaining to extraterrestrial life; typical of an extraterrestrial creature.

verb

1. (transitive) To estrange; to alienate.

2. (law) To transfer the ownership of something.