Definition of: umbrella

(um·brel′ə) noun
1. A light portable canopy on a folding frame, carried as a protection against sun or rain.
2. Zool. The contractile, jellylike portion of the body of a medusa expanded like a bell or umbrella.
3. Something serving as a cover or shield, or as a means of linking together various things under a common designation or sponsoring agency: the expanding umbrella of nuclear power; various theater groups appearing under the umbrella of UNESCO.
—adjective Being or serving as an umbrella (def. 3): an umbrella organization; an umbrella statement. [<Ital. ombrella, alter. (after ombra shade) of L umbella parasol. Related to UMBEL.]