Aequi.

The name is of unclear origin, but likely from Aequian. The extended version of their name, Aequīculi, possibly derives from a locative form of aequum (“plain”), suggesting they were initially "inhabitants of the plain." However, historically, they resided in predominantly hilly regions. The presence of the -q- in the name might trace back to a Proto-Indo-European *kʷ-. This suggests a connection to the Latin family, which retains this sound, unlike the Volscian, Umbrian, and Samnite dialects where it becomes p- (e.g., Latin quis versus Oscan 𐌐𐌉𐌔 (pis)). Alternatively, the *kʷ- could stem from an original Indo-European "k" + "u" combination, akin to the transformation seen in Latin equus and Umbrian 𐌄𐌊𐌅𐌏𐌍 (ekvon). Although the adjective Aequicus could imply a relationship with the Volscians or Sabines, it does not seem to have been used as an actual ethnic designation.