exo-

a combining form meaning “outside,” “outer,” “external,” used in the formation of compound words:

exocentric.

Also, ex-.

Origin

< Greek, combining form of éxō outside

British Dictionary definitions for exo-

combining form

external, outside, or beyond: exobiology, exothermal

Word Origin

from Greek exō outside

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-).

exo- in Medicine

exo- pref.
Outside; external: exoskeleton.

exo- in Science

exo-
A prefix that means "outside" or "external," as in exoskeleton.