Any path through an otherwise obstructed space.
Seat in public transport, such as a plane, train or bus, that's beside the aisle.
A clear corridor in a supermarket with shelves on both sides containing goods for sale.
A wing of a building, notably in a church separated from the nave proper by piers.
The path of a wedding procession in a church or other venue; (by extension, metonymically) marriage.
An idiomatic divide between the Republican Party and the Democratic Party, who are said to be on two sides of the aisle.
A clear path through rows of seating.
A slightly elevated path for pedestrians over sandy or swampy ground, typically made out of wood; specifically (Canada, US) one running alongside a body of water or beach.
To install a boardwalk over.