Definition of alien
(Entry 1 of 3)
1a
: belonging or relating to another person, place, or thing : strange
an alien environment
b
: relating, belonging, or owing allegiance to another country or government : foreign
alien residents
c
: exotic sense 1
alien plants
d
: coming from another world : extraterrestrial
alien beings an alien spaceship When it comes to knowing what alien life forms might be like, we don't have any idea.— Kate Shuster
2
: differing in nature or character typically to the point of incompatibility
ideas alien to democracy
alien
nounDefinition of alien (Entry 2 of 3)
1a
: a person who is not of a particular group or place
aliens seeking asylum in the U.S. In this way it came to pass that those scattered linen-weavers—emigrants from the town into the country—were to the last regarded as aliens by their rustic neighbours …— George Eliot … she whom we had deemed so … pious, at last died an alien from the church …— Delia Salter Bacon
b
: a foreign-born resident who has not been naturalized and is still a subject or citizen of a foreign country
broadly
: a foreign-born citizen
2
: extraterrestrial
a movie about an invasion of Earth by monstrous aliens
3
: exotic sense 1
Russian thistle, kudzu, and other aliens
alien
verb
aliened; aliening; aliens
Definition of alien (Entry 3 of 3)
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Merriam-Webster unabridged
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Time Traveler for alien
The first known use of alien was in the 14th century
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