Pierdominici is a rare Italian surname, not documented as an autonomous entry in the classic onomastic repertoires consulted. The structure of the surname is formed by the union of two medieval personal names, Pier (the short Italian form of Pietro or Piero, from the Latin Petrus, from the Greek Pétros, 'stone', linked to the apostle Saint Peter) and Dominici (the patronymic plural form of Domenico, from the Christian Latin Dominicus, 'of the Lord', consecrated to the Lord, linked to the cult of Saint Dominic of Guzmán and to the Sunday festivity).

The compound Pierdominici would literally mean Pier son of Domenico or of the family Pier dei Domenici, characteristic of the medieval onomastics of central Italy where the combination of two names as a surname was a practice documented from the 13th century.

The distribution of the surname Pierdominici is reduced and concentrated in the Marche, Umbria and Abruzzo, areas of greatest historical diffusion of the name Domenico.