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blue moon
[ bloo-moon ]
/ ˈblu ˈmun /
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idiom
a very long period of time: Such a chance comes once in a blue moon.
QUIZ
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Origin of blue moon
First recorded in 1815–25
Words nearby blue moon
blue melilot, blue merle, blue mockingbird, blue mold, blue Monday, blue moon, blue mould, Blue Mountains, blue mud, blue murder, blue myrtle
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use blue moon in a sentence
British Dictionary definitions for blue moon
blue moon
noun
the second full moon occurring within a calendar month
once in a blue moon informal very rarely; almost never
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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