Umbra

WORD OF THE DAY

umbra / noun / UM-bruh

Definition

1a: a conical shadow excluding all light from a given source 

1b: the conical part of the shadow of a celestial body excluding all light from the primary source

1c: the central dark part of a sunspot

2: a shaded area

Examples

"Thus far, though, no one on the ISS has managed to 'thread the needle,' with a view passing through the narrow umbra of a total solar eclipse." 

— David Dickinson, Sky & Telescope, 4 Aug. 2017

"A penumbral lunar eclipse is scheduled for Friday (Jan. 10). No part of the moon enters Earth's much darker umbra, as happens during a partial or total lunar eclipse. But on Jan 10-11 (depending on your location), just about the best penumbral eclipse possible will occur." 

— Joe Rao, Space.com, 9 Jan. 2020

Did You Know?

The Latin word umbra ("shade, shadow") has given English a range of words in addition to umbra itself. An umbrella can provide us with shade from the sun. So can an umbrageous tree. (In this case, umbrageous means "affording shade.") 

The connection to shade or shadow in other umbra words is less obvious. When we say someone takes umbrage, we mean they take offense, but in times past people used the word as a synonym of shade or shadow. 

These two senses of umbrage influenced umbrageous, which can mean "inclined to take offense easily" as well as "affording shade."