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xero-

American  
especially before a vowel, xer-.
  1. a combining form meaning “dry,” used in the formation of compound words.

    xerophyte.


xero- British  

combining form

  1. indicating dryness

    xeroderma

"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 xero- mean? Xero- is a combining form used like a prefix meaning “dry.” It is often used in scientific terms, including in pathology and ecology.Xero- comes from the Greek xēros, meaning “dry.”What are variants of xero-?When combined with words or word elements that begin with a vowel, xero- becomes xer-, as in xerarch.

Etymology

Origin of xero-

Combining form of Greek xērós dry