blood moon

variants: or Blood Moon
plural blood moons or Blood Moons

Definition of blood moon

: 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. (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.

First Known Use of blood moon

1817, in the meaning defined above

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The first known use of blood moon was in 1817

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Cite this Entry

“Blood moon.” Dictionary, Merriam-Webster, Accessed 27 Jul. 2021.

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