source
Spanish, Castilian
Spanish speaking countries
cuando las vacas vuelen *
* when cows fly
Expression used here and there by Everyone
Expression used when you want to emphasize that something is never going to happen. Oh well, maybe when cows fly.
"¿Mi madre dejarme ir al concierto de Maluma sola? Sí claro, cuando las vacas vuelen."
"My mother allowing me to go to Maluma's concert by myself? Yeah sure, when cows fly."
12 out of 16 Spanish, Castilian speakers have heard this