apple pie n 1: pie (with a top crust) containing sliced apples and sugar
Apple pie \Ap"ple pie`\ A pie made of apples (usually sliced or stewed) with spice and sugar. [1913 Webster] {Apple-pie bed}, a bed in which, as a joke, the sheets are so doubled (like the cover of an apple turnover) as to prevent any one from getting at his length between them. --Halliwell --Conybeare. {Apple-pie order}, perfect order or arrangement. [Colloq.] --Halliwell. [1913 Webster]