a combining form meaning “outside,” “outer,” “external,” used in the formation of compound words: exocentric.
English Affixes From A To Z: A One-Stop List Of Suffixes, Prefixes, and Combining FormsIn English, we love to make new words by adding all sorts of bits to the front and back of existing terms. These are called affixes, and they are added to the base or stem of a word. When attached to the end of word, the affix is called a suffix. And to the beginning? A prefix.
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
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.