umbra

noun um·bra \ ˈəm-brə \

Definition of umbra

plural umbras or umbrae play \ˈəm-(ˌ)brē, -ˌbrī\

1 :a shaded area

2 a :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

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umbral

play \ˈəm-brəl\ adjective

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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 of umbra from the Web

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
The line of totality will be inside the moon's umbra, or deep shadow.

— julie washington, cleveland.com, "Solar eclipse 2017 Q&A: Sunglasses, schedule, photography, map (video)," 16 Aug. 2017
According to Space.com, the three do not align perfectly, leaving a small area of the moon's shadow covered by a dark part of the Earth's shadow - the umbra.

— AL.com, "Inmate escapes from a work release center in Decatur," 7 Aug. 2017
Earth’s shadow has two parts: the umbra, which is the darker inner portion, and the penumbra, the lighter outer part.

— nicholas st. fleur, New York Times, "Partial Lunar Eclipse Will Shadow the Moon on Monday," 4 Aug. 2017
The nearest area in the umbra to Sacramento is about 400 miles away along the totality path in Oregon.

— carolyn wilke, sacbee, "What you need to know about the total solar eclipse," 1 Aug. 2017
So our next step was to filter the entire zone down to just public land, using a pair of mapping code libraries to analyze the topology of just the area inside the umbra.

— chris wilson, Time, "Here's How Everyone in the U.S. Could Witness the Total Solar Eclipse in Person," 25 July 2017
The moon casts its dark central shadow, called the umbra, onto a very narrow strip along the surface of the Earth.

— National Geographic, "In Case You Missed It: Stunning Photos of Rare Solar Eclipse," 9 Mar. 2016

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.

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."