Definition of pie:
(n) :
a type of
pastry that consists of an outer crust and a
filling; extended to other, non-pastry dishes that maintain the general concept of a shell with a filling
"the family had steak and kidney pie for dinner and cherry pie for dessert."
(v) :
to hit in the face with a pie, either for comic effect or as a means of protest (see also
pieing); to go around (a corner) in a guarded manner
"I'd like to see someone pie the chairman of the board."