once in a blue moon
/ˌwʌns ɪn ə ˌbluː ˈmuːn/INFORMAL · B2
Meaning
very rarely
Examples
- 1We only eat out once in a blue moon, so tonight feels special.
- 2My brother lives in Canada, so I see him once in a blue moon.
- 3Priya is always on time; she's late once in a blue moon, and only when the trains are cancelled.
- 4Does Grandad still go to the cinema, or only once in a blue moon these days?
- 5The big supermarket is miles from the village, so the family drives there once in a blue moon.
Grammar
The phrase does not change. It usually comes at the end of a clause.
More idioms about colours
All 20 idioms and the topic quiz →a white liea small untruth told to avoid hurting someonegreen with envyvery jealous of what someone else hassee redto suddenly become very angrywith flying coloursvery successfully, especially in a testa grey areaa situation where the rules are not clearget the green lightto be given permission to start
English Idioms400 idioms in 20 topics — with reviews that keep them from fading
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