once in a blue moon

idiom

Definition of once in a blue moon

: very rarely It happens once in a blue moon.

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once-born

once in a blue moon

once in a lifetime

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Cite this Entry

“Once in a blue moon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/once%20in%20a%20blue%20moon. Accessed 5 Jul. 2022.

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