The authors agree that this surname is related to the Latin feminine name clara, meaning "luminous" or "splendid", linked historically to the figure of Saint Clare of Assisi. A. Bongioanni notes that the name is of Latin origin and that its use as a given name spread also in the masculine in Tuscany, giving rise to variants such as Chiarella, Chiarini and Chiarotti; in Piedmont it appears as Clara and Clarotti, and in Friuli as Claricini, derived from Clarice or Clarissa, names present in several medieval chansons de geste. F. Miranda agrees with this etymological line and adds that the surname could have been adopted out of religious devotion or in allusion to physical or moral qualities.

E. Rossoni does not rule out, however, that the surname may derive from any of the multiple Italian place names that contain the root Chiara, which would open an origin independent of the anthroponym. The surname presents multiple independent clusters of origin (ceppi), arisen in different regions without direct relation between them, with presence documented in Piedmont, Veneto, Puglia and Sicily.

For the Sicilian case, V. Blunda proposes a different etymology of a dialectal character: the surname would derive from the Sicilian word chiàra, meaning "gravel" or "pebble", referring to the stony material that formed the bed of the torrents and was used in rustic constructions. In this interpretation, the surname would have arisen as a microtoponym applied to the one who lived beside a stony watercourse, or as reference to a trade linked to that material. Blunda considers that the association with the feminine personal name Clara constitutes, in the Sicilian context, a false etymology.