What term describes a structure that surrounds a French window or door without being supported by pillars?

The term that describes a structure surrounding a French window or door without being supported by pillars is known as a balcony. A balcony is typically an elevated platform that projects from the wall of a building and is enclosed by a railing. Unlike a patio or veranda, which are usually at ground level and often supported by structures like pillars, a balcony specifically refers to that elevated space often associated with upper stories of buildings.

In the context of architecture, balconies serve both aesthetic and functional purposes, providing a space for outdoor activities while offering an elevated view of the surroundings. The other options listed do not accurately describe this feature; for instance, a patio is a ground-level outdoor space, a veranda is a roofed structure extending along the outside of a building but typically supported by columns, and a gallerie often refers to a long passageway or gallery, which is distinct in its use and structure.