Cai

/KYE/

WelshBoy

Cai is a Welsh boy's name pronounced /KYE/. A classic Welsh name derived from the Latin Gaius, meaning rejoice.

Meaning of Cai

A classic Welsh name derived from the Latin Gaius, meaning rejoice.

Cai is a traditional Welsh name derived from the Latin name Gaius, which originates from the verb 'gaudere' meaning 'to rejoice'. In Welsh mythology and Arthurian legend, Sir Kay (Cai Hir) was King Arthur's foster brother and seneschal, appearing as a heroic figure in the Mabinogion.

Origin
Welsh
Pronunciation
/KYE/

Cultural background

The name remains highly popular in Wales and among Welsh-speaking communities, often chosen for its brevity and deep connection to Celtic folklore.

Variations & nicknames

  • Kai
  • Caius
  • Caio
  • Kay
  • Kaye

Famous people named Cai

Well-known namesakes — celebrities, historical figures and characters.

  • Cai Hir

    A prominent figure in Arthurian legend and the Mabinogion, known as Sir Kay.

    Literature/Mythology · Medieval

  • Cai Griffiths

    Professional Welsh rugby union player who played for the Ospreys.

    Sport · 2000s-present

  • Cai Evans

    Welsh professional rugby union player for the Dragons and the Wales national team.

    Sport · 2010s-present

Frequently asked about Cai

What does Cai mean?
Cai is a Welsh name meaning 'to rejoice', derived from the Latin name Gaius.
How do you pronounce Cai?
Cai is pronounced to rhyme with the English words 'sky' or 'pie' (/kaɪ/).
Is Cai a boy or girl name?
In Wales, Cai is traditionally and almost exclusively used as a boy's name.
Is Cai a common name in Wales?
Yes, it is a well-established and popular choice for boys in Wales and has consistently appeared in regional naming charts.

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