The building blocks of English
Affixes
exo-
External; from outside.
Greek exō, outside.
The great majority of words here are in modern technical and scientific usage; exceptions are exotic, which derives via Latin from Greek exōtikos, foreign, and exogamy (Greek gamos, marriage), the custom of marrying outside a community, clan, or tribe. Some examples of technical terms are exoskeleton, a rigid external covering for the body in some invertebrate animals; exothermic, of a chemical reaction or process that is accompanied by the release of heat; exogenous, developing from external factors; exobiology, the branch of science that deals with the possibility and likely nature of life on other planets or in space.
Its opposite is endo‑; see also ecto‑. Words such as exorbitant or exonerate instead contain Latin ex‑ (see ex‑1); some, such as exodus or exorcize, come from Greek (see ex‑2).
Support this website
This dictionary contains more than 1,250 entries, illustrated by some 10,000 examples, all defined and explained for your information and emjoyment.
There are no advertisements to interrupt your reading pleasure. I rely on your generosity to cover running costs. Donations made via PayPal are secure.