n.
In Classical architecture , a triangular gable crowning a portico or facade.
The pediment was the crowning feature of the Greek temple front. The pediment's triangular wall surface, or tympanum, was often decorated with sculpture. The Romans adapted the pediment as a purely decorative form to finish doors, windows, and niches, sometimes using a series of alternating triangular and segmentally curved pediments, a motif revived in the Italian High Renaissance. Baroque-era designers developed many varieties of broken, scrolled, and reverse-curved pediments.