BriallenfWelsh (Rare) Derived from Welsh briallu meaning "primrose". This is a modern Welsh name.
CadellmWelsh (Rare) From Old Welsh Catell, derived from cat"battle" and a diminutive suffix. This was the name of two early kings of Powys in Wales.
CadeyrnmWelsh (Rare) From Old Welsh Catigirn meaning "battle king", derived from cat "battle" and tigirn "king, monarch". This was the name of a 5th-century king of Powys in Wales, the son of Vortigern.
CadfaelmWelsh (Rare) From Old Welsh Catmail meaning "battle prince", from cat "battle" and mael "prince". This was apparently the birth name of Saint Cadoc. It was used by the British author Ellis Peters for the main character in her books The Cadfael Chronicles, first released in 1977.
CadwganmWelsh (Rare) From Old Welsh Catguocaun (and many other spellings) meaning "glory in battle", from cat "battle" and guocaun "glory, honour". It appears briefly in the medieval Welsh tale The Dream of Rhonabwy.
EifionmWelsh From an Old Welsh given name of unknown meaning, the source of the place name Eifionydd (also called Eifion) in northwestern Wales. This name was revived in the 19th century, probably via the place name.
GwenfrewifWelsh (Rare) Derived from Welsh gwen meaning "white, blessed" combined with another element of uncertain meaning. It could possibly be Welsh ffreu meaning "stream, flow" or the obscure word ffrewi meaning "pacify, quell, reconcile". This may be the original form of Winifred. In any case, it is the Welsh name for the saint.
RhydderchmWelsh (Rare) From the Old Welsh name Riderch, probably derived from ri "king" combined with derch "exalted". Rhydderch Hael was a 6th-century king of Strathclyde. This name has sometimes been Anglicized as Roderick.
TudwalmWelsh (Rare) From the Old Welsh and Breton name Tutgual, derived from tut "people, country" and gual "ruler, leader". This was the name of a 6th-century Breton saint.