exo-

American  

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

   exocentric.

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exo ¹ British  

/ ˈɛksəʊ /

adjective

1. an informal word for excellent

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exo- ² British  

combining form

1. external, outside, or beyond

   exobiology

   exothermal

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exo– Scientific  

1. A prefix that means “outside” or “external,” as in exoskeleton.

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Etymology

Origin of exo-

< Greek, combining form of éxō outside