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“Variant of Gaius — rejoicing (from Proto-Indo-European *geh₂w- 'to rejoice')” — Latin (praenomen; archaic spelling of Gaius) origin
Boy's name · #927 in the US (2025) · Trending
Caius is moving up the charts. First recorded in 1994, it stood at #927 in 2025 — its strongest showing yet; about 2,300 boys have been named Caius along the way. Together with its spelling variant Kaius (#1029), Caius would rank around #605 with about 470 births last year — the newborns split about 54/46 between Caius and Kaius.
Around the world: about 1 in 2,800 boys in N. Ireland (2025) · about 1 in 7,900 boys in Canada (2024) · about 1 in 8,800 boys in England & Wales (2025).
Appears in 2020-2025 birth records of 20 states. See the full state-by-state map on this page.
Among 27 notable people named Caius:
Political leaders appear 2.16× more often than among typical names — e.g. Caius Furius Pacilus Fusus, 5th-century BC Roman statesman and consul.
Similar names: Kaius · Beaux · Kaisen · Denim · Aurelius · Calum
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