10
extraterrestrial(noun, adjective, unknown, extraneous, celestial)
9
alienate(verb, phrasal verb, law, give, separate)
9
extraterrestrial being(noun, expression, idiom)
9
interloper(noun, being, people, attacker, visitor)
8
estrange(verb, separate, destroy, alienate, disaffect)
8
inappropriate(adjective, obscure, unusual, strange, fantastic)
8
outside(adjective, separate, obscure, experience, different)
8
unrelated(adjective, obscure, strange, awkward, fantastic)
8
bizarre(adjective, obscure, unusual, strange, new)
8
cede(verb, law, change, give, abandon)
8
convey(verb, phrasal verb, law, give, abandon)
8
disaffect(verb, separate, withdraw, alienate, divorce)
8
emigrant(noun, person, extraneousness)
8
hostile(adjective, mean, nasty, cold, unfriendly)
8
irrelevant(adjective, awkward, distant, mysterious, unknown)
7
adverse(adjective, mean, bad, nasty, disgusting)
7
noncitizen(noun, being, foreigner, stranger, weeds)
7
unusual(adjective, obscure, strange, new, different)
7
transfer(verb, phrasal verb, law, give, abandon)
7
unfriendly(adjective, mean, bad, nasty, cold)
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APASmart Define. (2016). alien thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/alien/thesaurus/synonyms
ChicagoSmart Define. 2016. "alien thesaurus" https://smartdefine.org/alien/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, alien thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/alien/thesaurus/synonyms>.
MLASmart Define. "alien thesaurus" 13 February 2016. Web. 22 September 2026. <https://smartdefine.org/alien/thesaurus/synonyms>