Cavall (Middle Welsh: cauall RBH & WBR; modernized: Cafall; pronunciation: /kaˈvaɬ/; Latin: Cabal, var. Caball (ms.K))) is the name of Arthur's dog, used in the hunt for the great boar, Twrch Trwyth (Latin: Troynt, Troit).
Cavall was Arthur's "favourite dog", and during a stag hunt, he was customarily the last dog to be let loose to chase after the game (Gereint Son of Erbin).
Legend in antiquity has it that Cabal left his permanent footprint in the rock while pursuing the boar Troynt. The lore is preserved in the (De Mirabilibus Britanniae or Mirabilia in shorthand) appended to Historia Brittonum (9th century). The wonderous nature of this cairn of stones was that even if someone removed that footprinted stone to another spot, it would be back at its original heap the next day.
The Latin account has the mark of age, since it refers to Arthur merely as warrior and not king. The full quote in translation is given in the Twrch Trwyth (or ), but Lady Guest's notes might best be consulted, since it provides both the Latin text and translation, as well as commentary on the Carn Cavall as well (Schreiber 1849, pp. 358–360).
Unlike the simple primitive lore, the late Welsh romance Culhwch and Olwen weaves a much more intricate tale, naming many dogs besides Cavall in the hunting party, and the is no longer just the boar Twrch Trwyth itself, its seven offspring (with names), and yet another boar named Yskithyrwyn besides.