O'Rorkes the, of Breffny, [53], [205], [527], [545]

O'Rorke, Brian, poem to, [520]

O'Ryans, the, [610]

O'Seasnan, poet, [446]

O'Shaughnessies, the, [33]

O'Sheas, the, [65]

Osgar an fléau [na suiste], [27]

Ossian, or Oisín, Finn Mac Cúmhail's son, [364]; his daughter married to Cormac Cas, ancestor of the Dalcassians, [76], Macpherson's Ossian, [364]; oldest poems ascribed to, [381]; meets Patrick, [383]; lives in Tir na n-óg, [498], [601]; dialogue with St. Patrick, [501]; complaint of, in his old age, [508]

Ossianic poetry, [466], [498] ff; its subject matter, [499]; half-acted, [511]; authorship of, [512]; largely post-Danish, [513]; list of poems, [513]; imitation Ossianic poem, [597], [601]; orally preserved, [606], [628]

O'Sullivans, the, [32], [62], [477]