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)
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
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
BreakingNews.ie Examples of blood moon in a Sentence
Recent Examples on the Web
In the meantime, here are some must-see photos of the blood moon lunar eclipse from around the world.
—Valerie Mesa, PEOPLE, 8 Sep. 2025
This thoughtful composition from Yang Bo was taken in the sky over Nanjing, China during totality, creating the illusion that the blood moon is being grasped in the claw of a vast stone dragon.
—Anthony Wood, Space.com, 8 Sep. 2025
That one will also bring a blood moon lasting nearly an hour.
—Jamie Carter, Forbes.com, 7 Sep. 2025
Total lunar eclipses are commonly referred to as blood moons because the moon turns a reddish color during the event.
—Melina Khan, USA Today, 6 Sep. 2025
Total lunar eclipses—and blood moons as a result—are even more rare with only about 29 percent of all lunar eclipses being total eclipses.
—Opheli Garcia Lawler, Travel + Leisure, 6 Sep. 2025
Why is a total lunar eclipse called a blood moon?
—Marina Johnson, Louisville Courier Journal, 5 Sep. 2025
This alignment causes Earth’s shadow to fall on the moon’s surface, turning it a rusty red — a phenomenon known as a blood moon.
—Diana Leyva, Nashville Tennessean, 5 Sep. 2025
Is there a blood moon in September 2025?
—Tiffany Acosta, AZCentral.com, 3 Sep. 2025
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Valerie Mesa, PEOPLE, 8 Sep. 2025
This thoughtful composition from Yang Bo was taken in the sky over Nanjing, China during totality, creating the illusion that the blood moon is being grasped in the claw of a vast stone dragon.
—Anthony Wood, Space.com, 8 Sep. 2025
That one will also bring a blood moon lasting nearly an hour.
—Jamie Carter, Forbes.com, 7 Sep. 2025
Total lunar eclipses are commonly referred to as blood moons because the moon turns a reddish color during the event.
—Melina Khan, USA Today, 6 Sep. 2025
Total lunar eclipses—and blood moons as a result—are even more rare with only about 29 percent of all lunar eclipses being total eclipses.
—Opheli Garcia Lawler, Travel + Leisure, 6 Sep. 2025
Why is a total lunar eclipse called a blood moon?
—Marina Johnson, Louisville Courier Journal, 5 Sep. 2025
This alignment causes Earth’s shadow to fall on the moon’s surface, turning it a rusty red — a phenomenon known as a blood moon.
—Diana Leyva, Nashville Tennessean, 5 Sep. 2025
Is there a blood moon in September 2025?
—Tiffany Acosta, AZCentral.com, 3 Sep. 2025
Cite this Entry
“Blood moon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/blood%20moon. Accessed 10 Sep. 2025.
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