Gaius

• (praenominal abbreviation): C., G. (less frequently)
• (archaic or hypercorrect): Cāius, Cājus
• Gājus

For Gāvius, from Proto-Indo-European *geh₂w- (“to rejoice”). Cognate with gaudeō, gaudium. Cognate with Etruscan 𐌂𐌀𐌄 (cae).

• (Classical) IPA^(key): /ˈɡaː.i.us/, [ˈɡäːiʊs̠]
• (modern Italianate Ecclesiastical) IPA^(key): /ˈɡa.i.us/, [ˈɡäːius]
• (Late Latin, common variant) IPA^(key): /ˈɡai̯.i̯us/, [ˈɡäi̯ːʊs̠]

Gāius m (genitive Gāiī or Gāī, feminine Gāia); second declension

1. A masculine praenomen, in particular:

   Qui totus servatus est in Gaiorum et Quintorum laterculis.^source

   Which was kept in its entirety on the registers of Gaiuses and Quintuses.

   1. Gaius (an eminent jurist who lived in the second century A.D.)
   2. Caligula, the emperor Gaius Julius Caesar Augustus Germanicus

• 1876, "C" in the Encyclopædia Britannica, 9th ed., Vol. IV, page 616:

  The symbol [C] retained its old value [/ɡ/] only when as the initial letter it represented the names Gaius and Gnæus, which, in consequence, are often erroneously written and sounded Caius and Cnæus.

Second-declension noun.

¹Found in older Latin (until the Augustan Age).
The noun Gāius possesses several irregularly syncopated forms in the nominative, dative, ablative, and vocative plural.

• Gāia f (praenomen)
• Gāiānus (“of, pertaining to Caligula”, adjective)
• Gāīpor (“male slave of Gaius”)

• → German: Gajus
• → Indonesian: Gayus
• → Ancient Greek: Γάϊος (Gáïos)
• → Coptic: ⲅⲁⲓⲟⲥ (gaios)
• → Etruscan: 𐌂𐌀𐌉𐌄 (caie)
• Georgian: გაიუსი (gaiusi)
• Italian: Caio
• Portuguese: Gaio, Caio
• Russian: Гай (Gaj) (possibly)
• Spanish: Gayo

• “Gaius”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• Gaius in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.