gable

The triangular upper portion of a wall to carry a pitched roof.

gallery

A storey above the aisle, opening on to the nave, also called a tribune; it is as wide as the aisle below it, and usually has its own windows.

gesso

The prepared ground of plaster and size for painting.

groin-vault

A vault produced by the intersection at right angles of two tunnel vaults. The curved intersections are called groins.

guilloche

A geometric running ornament consisting of two or more intertwining bands.