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n. pl. um·bras or um·brae (-brē)
1. A dark area, especially the blackest part of a shadow from which all light is cut off.
a. The completely dark central portion of the shadow cast by the earth, moon, or other body during an eclipse.
b. The darkest region of a sunspot.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
n, pl -brae (-briː) or -bras
1. (Astronomy) 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
2. (Astronomy) the darker inner region of a sunspot
[C16: from Latin: shade, shadow]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
n., pl. -bras, -brae (-brē).
1. shade; shadow.
2. the usual accompaniment or companion of a person or thing.
a. the complete or perfect shadow of an opaque body, as a planet, where the direct light from the source of illumination is completely cut off.
b. the dark central portion of a sunspot.
4. a phantom or ghost.
[1590–1600; < Latin: shade, shadow]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
1. The darkest part of a shadow, especially the completely dark portion of the shadow cast by Earth, the moon, or another body during an eclipse.
2. The darkest region of a sunspot. Compare penumbra.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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|Noun||1.||umbra - a region of complete shadow resulting from total obstruction of light|
shadow - shade within clear boundaries
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
The American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.