(1):
(n.) A lateral division of a building, separated from the middle part, called the nave, by a row of columns or piers, which support the roof or an upper wall containing windows, called the clearstory wall.
(2):
(n.) Improperly used also for the have; - as in the phrases, a church with three aisles, the middle aisle.
(3):
(n.) Also (perhaps from confusion with alley), a passage into which the pews of a church open.