Umbriel

noun
Um·​bri·​el | \ ˈəm-brē-ˌel How to pronounce Umbriel (audio) \

Definition of Umbriel

astronomy
: the third largest satellite of Uranus with a diameter of approximately 730 miles (1170 km) Earlier this year, Buratti and her co-workers reported other evidence suggesting that Umbriel might be a Uranian oddity. Analyzing photographs taken through various color filters by the Voyager 2 spacecraft, they found that the ratio of green light to violet light varies widely over Umbriel's surface.Science News, 16 Nov. 1991

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First Known Use of Umbriel

1874, in the meaning defined above

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The first known use of Umbriel was in 1874

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Dictionary Entries Near Umbriel

Umbridae

Umbriel

umbriferous

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Cite this Entry

“Umbriel.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Umbriel. Accessed 15 Aug. 2022.

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