umbrella

Concise Oxford English Dictionary © 2008 Oxford University Press:
umbrella/ʌmˈbrelə/

▶noun

• 1 a device consisting of a circular fabric canopy on a folding metal frame supported by a central rod, used as protection against rain.

• 2 a protecting force or influence.

  ■ a screen of fighter aircraft or anti-aircraft artillery.

• 3 [usu. as modifier] a thing that includes or contains many different parts: an umbrella organization.

• 4 Zoology the gelatinous disc of a jellyfish, which it contracts and expands to move through the water.

– derivatives
umbrellaed adjective.

– origin C17: from Ital. ombrella, dimin. of ombra ‘shade’, from L. umbra ‘shadow’.