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xeno-

American  
especially before a vowel, xen-.
  1. a combining form meaning “alien,” “strange,” “guest,” used in the formation of compound words.

    xenogamy, xenolith.


xeno- British  

combining form

  1. indicating something strange, different, or foreign

    xenogamy

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What does xeno- mean? Xeno- is a combining form used like a prefix meaning “alien,” “strange,” or “guest.” It is used in a variety of domains, including in botany, medicine, mineralogy, the social sciences, and zoology.Xeno- comes from the Greek xénos, a noun meaning “stranger, guest" or an adjective meaning “foreign, strange.” The name of the chemical element (and noble gas) Xenon also derives from the Greek xénos.What are variants of xeno-?When combined with words or word elements that begin with a vowel, xeno- becomes xen-, as in xenarthral.

Etymology

Origin of xeno-

Combining form of Greek xénos stranger, guest (noun); alien, foreign, strange (adj.)