once in a blue moon
Meaning: If something happens once in a blue moon, it happens very rarely.
- We hardly ever go out these days, though once in a blue moon we might go and see a movie.
- My daughter lives in Brazil and she only comes to see us once in a blue moon; maybe every two or three years if we're lucky.
We live in a town in the desert now. It's hot and dry most days, and once in a blue moon it will