Definition of alien :
1. A foreigner; one owing allegiance, or belonging, to another country; a foreign- born resident of a country in which he does not possess the privileges of a citizen. Hence, a stranger. See Alienage.
2. Not belonging to the same country, land, or government, or to the citizens or subjects thereof; foreign; as, alien subjects, enemies, property, shores.
3. One excluded from certain privileges; one alienated or estranged; as, aliens from God's mercies.
4. To alienate; to estrange; to transfer, as property or ownership.
5. Wholly different in nature; foreign; adverse; inconsistent ( with); incongruous; - followed by from or sometimes by to; as, principles alien from our religion.
unknown, cyberpunk, accidental, opposed, overseas, unknown region, cyborg, repugnant, odd, extraterrestrial being, outsider, newcomer, different, surprising, disaffect, adventitious, offbeat, notable, noncitizen, nonnative, gaijin, supervenient, terra incognita, dissimilar, ET, remarkable, unknown quantity, study at, alienate, native, beam down, beam up, MiGr, unusual, unique, estrange, out of the ordinary, android, earthling, special
aeronaut (part of speech: noun)
foreigner (part of speech: noun)
unrelated (part of speech: adjective)
extraneous (part of speech: adjective)
foreign, inappropriate, inadmissible, outer, extraterrestrial, eerie, nonessential, exotic, estranged, separated, foreign-born, extrinsic, disjoint, outlandish, strange, unaffiliated, immaterial, other, detached, impertinent, disaffiliated, parenthetical, outside, removed, segregated, inapplicable, separate, external, unessential, unallied, dissociated, extraneous, irrelevant, unrelated, disconnected
- It was the sense of an alien presence that caused my terror- a fear of the unknown.... - "Where the World is Quiet", Henry Kuttner.
- Nothing could have torn me from the spot but what precisely did, an alien intervention. - "Lore of Proserpine", Maurice Hewlett.
- But now he was flying an alien flag. - "The Hollow of Her Hand", George Barr McCutcheon.