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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.)