umbra

noun

um·​bra ˈəm-brə How to pronounce umbra (audio)
plural umbras or umbrae ˈəm-(ˌ)brē How to pronounce umbra (audio)
-ˌbrī
1
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
2
: a shaded area
umbral 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. These 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Because the moon will sit deep within Earth's umbra — the darkest part of our planet's shadow — expect a rich, dark red hue during totality. Daisy Dobrijevic, Space.com, 7 Sep. 2025 The umbra is a darker inner shadow and the penumbra is a fainter outer shadow, according to NASA. Melina Khan, USA Today, 6 Sep. 2025 During a total lunar eclipse, the moon passes through the darkest part of Earth’s shadow, known as the umbra. Diana Leyva, Nashville Tennessean, 5 Sep. 2025 The umbra is a darker inner shadow and the penumbra is a fainter outer shadow, according to NASA. Marina Johnson, Louisville Courier Journal, 5 Sep. 2025 See All Example Sentences for umbra

Word History

Etymology

Latin

First Known Use

1638, in the meaning defined at sense 2

Time Traveler
The first known use of umbra was in 1638

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Cite this Entry

“Umbra.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/umbra. Accessed 9 Sep. 2025.

Kids Definition

umbra

noun
um·​bra ˈəm-brə How to pronounce umbra (audio)
plural umbras or umbrae -brē How to pronounce umbra (audio)
-ˌbrī
1
: a shaded area
2
: the cone-shaped part of the shadow of a celestial body from which the light of the sun is completely blocked

More from Merriam-Webster on umbra

Last Updated: - Updated example sentences
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