blood moon

noun

variants or Blood Moon
plural blood moons or Blood Moons
: a full moon that coincides with a full lunar eclipse and that has an unusually reddish appearance

Note: The red color of a blood moon is caused by the diffusion of the sun's light into the shadow cast by the Earth.

And when it [the full moon] is eclipsed by the shadow of the Earth, it is called a blood moon as it turns a crimson color. IFLSCIENCE.com (London)
Through the little windows over the deep double kitchen sink, I saw a big sliver of blood moon sinking below the distant mountains. David Erik Nelson
also : a full lunar eclipse during which a blood moon occurs
A blood moon is the unscientific name for a total lunar eclipse, which is when Earth passes in between the sun and the moon, casting a shadow over the moon as sunlight is blocked. BreakingNews.ie

Examples of blood moon in a Sentence

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.
The first blood moon will occur between March 13–14 and will be best visible from North America, with totality lasting 65 minutes. Dan Perry, Newsweek, 2 Jan. 2025 This bathes our natural satellite in a rusty glow, giving this celestial event its more accurate nickname: a blood moon. Carlyn Kranking, Smithsonian Magazine, 30 Dec. 2024

Word History

First Known Use

1817, in the meaning defined above

Time Traveler
The first known use of blood moon was in 1817

Dictionary Entries Near blood moon

Cite this Entry

“Blood moon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/blood%20moon. Accessed 25 Jan. 2025.

Last Updated: - Updated example sentences
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