Other forms: aisles
An aisle is a passageway, often between seating areas or shelves. Brides and grooms walk down an aisle at weddings, while you might head to the cookie aisle in the supermarket.
An aisle is essentially a passageway between something. You have to walk down an aisle to reach your seat at a theater or concert hall, to get to your seat on a crowded airplane, or to reach the produce at your local supermarket. The ai in aisle is pronounced like a long i, so the word sounds like isle rather than ail.