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English definition of “once in a blue moon”

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once in a blue moon

not very often: My sister lives in Alaska, so I only see her once in a blue moon.
Translations of “once in a blue moon”
in Chinese (Traditional) 少有地…
in Russian раз в год по обещанию, очень редко…
in Turkish ayda yılda bir, kırk yılda bir, (argo) ölme eşeğim ölme…
in Chinese (Simplified) 少有地…
in Polish raz na ruski rok…
(Definition of once in a blue moon from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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