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
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before a vowel end-
Word Origin for endo-
from Greek, from endon within
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A prefix meaning inside, as in endoskeleton.
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