Save Gender Masculine Usage Arthurian Cycle Other Forms FormsDiones, Dionis, Dyounes, Ydones Meaning & History Brother of Alibel, Dion, and Casibilant, and nephew of Duke Calles.His six cousins revolted against their father. Dyonis and his brothers assisted Calles in the war, in which they were joined by Agravain, Gaheris, and Gareth.