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English definition of “alien”

alien

adjective     /ˈeɪ.li.ən/
coming from a different country, race, or group: an alien culture → Synonym foreignRacial issuesRace and ethnicity strange and not familiar: When I first went to New York, it all felt very alien to me.Unknown and unfamiliar [before noun] relating to creatures from another planet: an alien spacecraftStrange, suspicious and unnatural things and people
(Definition of alien adjective from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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