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exo-

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a combining form meaning “outside,” “outer,” “external,” used in the formation of compound words: exocentric.
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“Was” is used for the indicative past tense of “to be,” and “were” is only used for the subjunctive past tense.
Also ex-.

Origin of exo-

<Greek, combining form of éxō outside
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use exo- in a sentence

British Dictionary definitions for exo- (1 of 2)

exo
/ (ˈɛksəʊ) /

adjective
Australian an informal word for excellent

British Dictionary definitions for exo- (2 of 2)

exo-

combining form
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

Medical definitions for exo-

exo-

pref.
Outside; external:exoskeleton.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for exo-

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.
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