Gallery (a.) : A long and narrow corridor, or place for walking; a
connecting passageway, as between one room and another; also, a long
hole or passage excavated by a boring or burrowing animal.
Gallery (a.) : A room for the exhibition of works of art; as, a picture gallery; hence, also, a large or important collection of paintings, sculptures, etc.
Gallery (a.) : A long and narrow platform attached to one or more sides of public hall or the interior of a church, and supported by brackets or columns; -- sometimes intended to be occupied by musicians or spectators, sometimes designed merely to increase the capacity of the hall.
Gallery (a.) : A frame, like a balcony, projecting from the stern or quarter of a ship, and hence called stern gallery or quarter gallery, -- seldom found in vessels built since 1850.
Gallery (a.) : Any communication which is covered overhead as well as at the sides. When prepared for defense, it is a defensive gallery.
Gallery (a.) : A working drift or level.