once in a blue moon

phrase

Synonyms of once in a blue moon next

: very rarely

It happens once in a blue moon.

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once in a lifetime

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“Once in a blue moon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/once%20in%20a%20blue%20moon. Accessed 9 Mar. 2026.

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once in a blue moon

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