The author of
De Praenominibus ("Concerning Praenomina") states that Gaius is derived from the same root as
gaudere, "to rejoice". Although Paris and the unidentified authorities whom he consulted probably relied on
folk etymology, modern scholars generally concur with this derivation. The original form of the name was probably
Gavius, in which form it was also used by the
Oscans; in
Faliscan it appears as
Kavios on the fifth-century BC Acquoria Cippus. However, in Latin it had already lost its medial "v" by the time of the earliest inscriptions. The older three-syllable pronunciation given above, in which the long "a" and short "i" are pronounced as full vowels: , is evidence of the original form. This pronunciation persisted, alongside the later two-syllable form in which "a" and "i" have concatenated to a diphthong: , throughout the period of the
Roman Republic. The existence of the patronymic
gens Gavia also indicates the original form of the name, although it could be argued that this family's name was derived from the Oscan praenomen
Gavius. But as
Gaius and
Gavius are apparently based on the same root, this distinction is of limited importance. In the form
Cae, this praenomen was also popular amongst the
Etruscans, who borrowed many names from both Latin and Oscan. == Derived names ==