- a walkway between or along sections of seats in a theater, classroom, or the like.
- a longitudinal division of an interior area, as in a church, separated from the main area by an arcade or the like.
- any of the longitudinal divisions of a church or the like.
- in the aisles, (of an audience) convulsed with laughter.
- a passageway separating seating areas in a theatre, church, etc; gangway
- a lateral division in a church flanking the nave or chancel
- rolling in the aisles informal (of an audience) overcome with laughter
late 14c., ele, “lateral division of a church (usually separated by a row of pillars), from Old French ele “wing (of a bird or an army), side of a ship” (12c., Modern French aile), from Latin ala, related to axilla “wing, upper arm, armpit; wing of an army,” from PIE *aks- “axis” (see axis), via a suffixed form *aks-la-. The root meaning in “turning” connects it with axle and axis.
Confused 15c. with unrelated ile “island” (perhaps from notion of a “detached” part of a church), and so it took an -s- when isle did, c.1700; by 1750 it had acquired an a-, on the model of French cognate aile. The word also was confused with alley, which gave it the sense of “passage between rows of pews or seats” (1731), which was thence extended to railway cars, theaters, etc.