The Probert Encyclopaedia of Architecture

GABLE

In architecture a gable is the vertical triangular portion of the end of a building, from the level of the cornice or eaves to the ridge of the roof. The name is also, given to a similar end when not triangular in shape, as of a gambrel roof and the like. Hence the term applies to the end wall of a building, as distinguished from the front or rear side, and a decorative member having the shape of a triangular gable, such as that above a Gothic arch in a doorway.
Research Gable