0 said when you cannot answer a question about the length, size, amount, etc. of something because it could be any length, size, etc.: --
And the cost? How long is a piece of string?
Asked how long this will take, she replies: "How long is a piece of string?"
NYA ORD
European
May 10, 2021
DAGENS ORD
Shimmer
how long is a piece of string?