Patrick Weston Joyce

Offaly, baronies of, in Kildare. The descendants of Ros-failghe [faly] or Ros of the rings, the eldest son of Cahirmore (king of Ireland from A.D. 120 to 123) were called Hy Failghe (The Topographical Poems of O'Dugan and O'Heerin), i. e. the descendants of Failghe (see Iverk); and a portion of their ancient inheritance still retains this name, in the modernized form Offaly.