Probably a corruption of 'pyramid,' reshaped by association with Latin pes 'foot,' for the triangular gable of a classical building.
The triangular upper part of the front of a classical building, typically surmounting a colonnade.
Probably an alteration of 'periment,' itself a corruption of 'pyramid.' The word emerged in English architectural writing in the 1660s, likely influenced by Latin pedāmentum 'prop, support' (from pes 'foot'). The triangular gable of a Greek temple was originally called the tympanon (drum). Key roots: *ped- (Proto-Indo-European: "