Kings: G

Mac Giolla Righ, Gilray (Devoted to the King) Giolla-ruaidh, Gilroy (The Red-haired Youth)
When an adjective, signifying a color or quality of the mind or body, is postfixed to Giolla, then it has its ancient signification-namely, a youth, a boy, or a man in his bloom ; Giolla-ruadh, i.e. the red-haired youth; Giolla-riabhach, the swarthy youth; Giollabuidhe, the yellow youth. Mall, Maul, Molle, and Molly, would suggest a derivation from Maol, Mael, or Moel, which was anciently prefixed, like Giolla, to the names of saints, to form proper names of men, as MAOLCOLAIM, The word Mael means silver. The world Molle, means Dust (73, 100)

[French Ministry of Education Site: Centre national de documentation pédagogique]