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"An ancient Greek or Roman temple, of rectangular construction, is terminated at its upper extremity by a triangular figure, both in front and rear, which rests upon the cornice of the entablature as a base, and has its sides formed by the cornices which terminate the roof. The whole of this triangle above the trabeation is implied in the term fastigium." — Smith, 1873.

Fastigium

"An ancient Greek or Roman temple, of rectangular construction, is terminated at its upper extremity…