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1.
A saying used to illuminate the issue of letting pie go stale. Pie is used as a noun in this form, and refers to a conversation held by close friends. When someone says "Let's not let this pie go stale, they are saying in fact that they do not want this conversation to get boring.
Abby: ....
Bob: .....
Joe: I'm bored of this pie....
Karen:.....
Abby: ...come on people
Abby: Let's not let this pie go stale!
by Kodiak The Bear May 26, 2009