External  —adj. 1 a of or on the outside or visible part. B coming from the outside or an outside source. 2 relating to a country's foreign affairs. 3 outside the conscious subject (the external world). 4 (of medicine etc.) For use on the outside of the body. 5 for students taking the examinations of a university without attending it. —n. (in pl.) 1 outward features or aspect. 2 external circumstances. 3 inessentials.  externality n. Externally adv. [latin externus outer]