umbra

noun
um·​bra | \ˈəm-brə \
plural umbras or umbrae\ ˈəm-​(ˌ)brē , -​ˌbrī \

Definition of umbra 

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

b : the central dark part of a sunspot

2 : a shaded area

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Other Words from umbra

umbral \ ˈəm-​brəl \ adjective

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

Examples of umbra in a Sentence

strange noises were coming from the wooded umbra beyond our campfire during a solar eclipse observers located within the umbra experience a complete blocking of the sun by the moon

Recent Examples on the Web

The moon will have finished its traversing of the Earth’s shadow, or umbra. Brian Resnick, Vox, "The longest lunar eclipse of the century will be on July 27," 24 July 2018 But, unlike a normal full moon that reflects the sun’s illumination, during a lunar eclipse, the moon emanates the Earth’s shadow (known as the umbra). Aliza Kelly Faragher, Allure, "A Beginner's Guide to Eclipses in 2018 and How They Can Affect Your Life," 16 July 2018 Under the umbra, however, things will stay around 85 degrees Fahrenheit, perfect beach weather. David Grossman, Popular Mechanics, "Upcoming Solar Probe Gets Its All-Important Heat Shield," 9 July 2018 The moon will begin to move into the umbra at around 3:48 a.m. PT, and totality—when the moon will appear red—will begin at 4:51 a.m. PT. Sarah Gray, Fortune, "Everything You Need to Know to Watch This Month's Supermoon Lunar Eclipse," 31 Jan. 2017 The full moon—in fact a supermoon and a blue moon—passed into Earth’s shadow or umbra, blocking the sun’s light, and making the surface of the moon appear a blood-red hue. Sarah Gray, Fortune, "See Stunning Photos of the Super Blue Blood Moon Lunar Eclipse," 31 Jan. 2018 The total eclipse, however, begins when the moon moves entirely into the direct shadow of the Earth, called the umbra. Jay Bennett, Popular Mechanics, "The Most Spectacular Eclipse of 2018 Is Tomorrow," 30 Jan. 2018 The umbra, or moon's shadow, passes over Earth during the total eclipse, as viewed from the International Space Station on August 21, 2017. Alan Taylor, The Atlantic, "Photos of the Week: 8/19–8/25," 25 Aug. 2017 On those clouds, bright sunshine defined the edges of the shadow — an elliptical cross-section of the moon’s conical umbra. Dominic Gates, The Seattle Times, "Alaska Airlines flight offers dramatic view of solar eclipse," 21 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'umbra.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of umbra

1638, in the meaning defined at sense 2

History and Etymology for umbra

Latin

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Dictionary Entries near umbra

umbone

umbonic

umbonulate

umbra

Umbracula

Umbraculidae

umbrage

Statistics for umbra

Last Updated

14 Nov 2018

Look-up Popularity

Time Traveler for umbra

The first known use of umbra was in 1638

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More from Merriam-Webster on umbra

Thesaurus: All synonyms and antonyms for umbra

Britannica English: Translation of umbra for Arabic Speakers

Britannica.com: Encyclopedia article about umbra

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