Yes, alien is playable
...and is worth 7 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Alien" Definition
noun
A creature from outer space: a story about an invasion of aliens.
A person from another and very different family, people, or place.
A person who is not included in a group; an outsider.
An unnaturalized foreign resident of a country. Also called noncitizen.
Ecology An organism, especially a plant or animal, that occurs in or is naturalized in a region to which it is not native.
adjective
Belonging to, characteristic of, or constituting another and very different place, society, or person; strange. See Synonyms at foreign.
Dissimilar, inconsistent, or opposed, as in nature: emotions alien to her temperament.
Owing political allegiance to another country or government; foreign: alien residents.
Belonging or relating to another person, place, or thing.
Relating, belonging, or owing allegiance to another country or government.
verb-transitive
Law To transfer (property) to another; alienate.
verb
To make over (as property).
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