[ uhm-bruh ]
/ ˈʌm brə /
noun, plural um·bras, um·brae [uhm-bree] /ˈʌm bri/.
the invariable or characteristic accompaniment or companion of a person or thing.
a phantom or shadowy apparition, as of someone or something not physically present; ghost; spectral image.
Words nearby umbra
Origin of umbra
1590–1600; < Latin: shade, shadow
OTHER WORDS FROM umbraum·bral, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for umbral
Outside the umbral cone is that of the penumbra, within which the sun is partially hidden by the moon.
British Dictionary definitions for umbral
/ (ˈʌmbrə) /
noun plural -brae (-briː) or -bras
a region of complete shadow resulting from the total obstruction of light by an opaque object, esp the shadow cast by the moon onto the earth during a solar eclipse
the darker inner region of a sunspot
Derived forms of umbraumbral, adjective
Word Origin for umbra
C16: from Latin: shade, shadow
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Science definitions for umbral
[ ŭm′brə ]
Plural umbras umbrae (ŭm′brē)
The darkest part of a shadow, especially the cone-shaped region of full shadow cast by Earth, the Moon, or another body during an eclipse. In a full lunar eclipse, which generally lasts for one or two hours, the entire disk of the Moon is darkened as it passes through the umbra. During this period the Moon takes on a faint reddish glow due to illumination by a small amount of sunlight that is refracted through the Earth's atmosphere and bent toward the darkened Moon; the reddish tint is caused by the filtering out of blue wavelengths as the sunlight passes through the Earth's atmosphere, leaving only the longer wavelengths on the red end of the spectrum. See Note at eclipse.
The dark central region of a sunspot. Compare penumbra.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.