- a combining form meaning “within,” used in the formation of compound words: endocardial.
Also especially before a vowel, end-.
Origin of endo-
< Greek, combining form of éndon within; cognate with Old Irish ind-, OL endo- in, on
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
before a vowel end-
- inside; withinendocrine
from Greek, from endon within
Word Origin and History for endo-
Online Etymology Dictionary, © 2010 Douglas Harper
- Inside; within:endometrium.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
- A prefix meaning inside, as in endoskeleton.
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