The Probert Encyclopaedia of Architecture

GALLERY

In architecture, gallaery is a long, narrow room, the length of which is at least three times its width, often built to receive a collection of pictures. The term gallery is also sometimes applied to what is more properly termed a corridor, likewise to a platform projecting from the walls of a building supported by piers, pillars, brackets, or consoles, and in churches, theatres, and similar buildings, to the upper floors going round the building next the wall.
Research Gallery