A magic female dog in Welsh legend.

Rhymhi lived in Aber Deu Cleddyf and had two pups that were sought by Arthur and his warriors, on the behalf of Culhwch, for the hunting of the boar Twrch Trwyth.

Curiously, the giant Ysbaddaden, who assigned the tasks to Culhwch, did not request these hounds, and it is unclear why Arthur and his soldiers decided that they had to obtain them.

Two of Rhymhi’s sons – Gwydden Astrus and Gwyddrud – were also said to be Arthur’s warriors.

The name Rhymi refers to a river in the Vita Sancti Cadoci.