see Achren.

Octriallach, son of Indech, [110];

the “Cairn of Octriallach”, [110].

O’Curry, Eugene, [37], [56], [63], [72], [78], [89], [93], [111], [113], [137], [138], [146], [151], [152], [155], [188], [201], [204].

Odin, [260].

O’Donaghue, the, [247].

O’Donovan, [238].

Oeth and Anoeth, the Bone-prison of, [270], [271], [317], [373].

O’Flynn, Eochaid, an old Irish poet, [231].

Ogam, writings in, [58], [93], [151], [189].