What is the difference between extraterrestrial and alien in terms of the usage of these two words?

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  • 2
    Context and research please. – Tushar Raj Jan 23 '17 at 8:31
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    There is a vast difference, depending on your context. – Hot Licks Jan 23 '17 at 13:40

Extraterrestrial very specifically refers to something which is not from planet Earth. Alien is a more general word which can be used in many contexts.


Not much. They are essentially synonymous.

The only substantial difference is that, in addition to referring to a being or creature from outer space, alien can also mean a foreigner, someone who isn't a naturalized citizen (noun) or odd, distasteful (adjective). Extraterrestrial doesn't have these additional meanings.


  • So, what is a human born on Mars? – Hot Licks Jan 23 '17 at 13:40
  • 1
    Confused and lonely? – freeling10 Jan 23 '17 at 14:43

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