a combining form meaning “outside,” “outer,” “external,” used in the formation of compound words: exocentric.
Origin of exo-
< Greek, combining form of éxō outside
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British Dictionary definitions for exo-
external, outside, or beyondexobiology; exothermal
Word Origin for exo-
from Greek exō outside
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
Word Origin and History for exo-
word-forming element used in scientific words (e.g. exoskeleton), from Greek exo "outside," related to ex "out of" (see ex-).
Online Etymology Dictionary, © 2010 Douglas Harper
Medicine definitions for exo-
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Science definitions for exo-
A prefix that means outside or external, as in exoskeleton.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.