Top definition
The act of a comeback to "why not" often used in a smart ass way to be funny and shut someone up from asking why.
Person 1: I'm sick.
Person 2: why?
Person 1: Why not?
Person 3: Why not not!
Person 1: .....what?
by BLEEDTeal36 June 22, 2011
Get the mug
Get a Why Not Not mug for your cousin James.