Dimiloc
A castle in Cornwall ruled by Gorlois, duke of Cornwall.
When King Uther Pendragon declared war against Gorlois over Igerne (Igraine), Gorlois’ wife, Gorlois sheltered her in Tintagel, his strongest castle, while Gorlois himself holed up in Dimilioc. Gorlois was eventually slain in a battle outside the castle.
Malory changes the castle’s name to Tarabel (Terrabil).
Source
Historia Regum Britanniae | Geoffrey of Monmouth, c. 1138