blue moon
noun
1
: a very long period of time
—usually used in the phrase once in a blue moon
such people happen along only once in a blue moon—
Saturday Rev.
Saturday Rev.2
: a second full moon in a calendar month
Synonyms
Examples of blue moon in a Sentence
once in a blue moon we'll get dressed up and eat in a fancy restaurant
Recent Examples on the Web
August's full moon has several names, including supermoon, blue moon and Sturgeon Moon.
—Marley Malenfant, Austin American-Statesman, 16 Aug. 2024
And whenever that happens, astronomers call the third full moon a seasonal blue moon.
—John Tufts, The Indianapolis Star, 7 Aug. 2024
There's also a lot of supermoons in 2024 — four in a row, in fact, which began in August with a rare seasonal blue moon.
—John Tufts, The Courier-Journal, 4 Sep. 2024
On Monday, a super blue moon lit up the night sky, giving people a glimpse at this rare spectacle.
—Marley Malenfant, Austin American-Statesman, 20 Aug. 2024
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Marley Malenfant, Austin American-Statesman, 16 Aug. 2024
And whenever that happens, astronomers call the third full moon a seasonal blue moon.
—John Tufts, The Indianapolis Star, 7 Aug. 2024
There's also a lot of supermoons in 2024 — four in a row, in fact, which began in August with a rare seasonal blue moon.
—John Tufts, The Courier-Journal, 4 Sep. 2024
On Monday, a super blue moon lit up the night sky, giving people a glimpse at this rare spectacle.
—Marley Malenfant, Austin American-Statesman, 20 Aug. 2024
See all Example Sentences for blue moon
Dictionary Entries Near blue moon
Cite this Entry
“Blue moon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/blue%20moon. Accessed 8 Feb. 2025.
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