when shrimps whistle

English

Etymology

Calque of Russian когда рак (на горе) свистнет (kogda rak (na gore) svistnet, “when the crawfish whistles (on the mountain)”)

Adverb

when shrimps whistle

1. (in Russian contexts) When pigs fly; never.
   • 2017 July 5, Francis R. Nicosia, The Three Romes: Moscow, Constantinople, and Rome, Routledge, →ISBN, page 64:

     You will catch her smiling at you, as Khruschchev used to say, when shrimps whistle. I call for a bowl of kasha and she brings it to the table. The cabbage soup is thickened with flour, a lump of meat swimming on the surface of the broth. Never mind the kasha, and I push it away. The babushka takes […]

   • 1965, Charles Burton Marshall, The Exercise of Sovereignty: Papers on Foreign Policy, page 110:

     These things will happen when shrimps whistle. Individuals and groups with divergent concepts of meaning and truth are likely to regard each other as prevaricators even when doing their respective best to be sincere.