Slechta: south-west of Kells, in Meath
Slemain Mide: "Slane of Meath," Slewen, three miles to the west of Mullingar, in Westmeath
Sliab Betha: Slieve Beagh, a mountain whereon the Counties of Fermanagh, Tyrone, and Monaghan meet
Sliab Culinn: Slieve Gullion, in the County Armagh
Sliab Fuait: the Fews Mountains, near Newtown-Hamilton, to the west and north-west of Slieve Gullion; in the southern part of the County Armagh
Sliab Mis: Slieve Mish, a mountain in the County Kerry, extending eastwards from Tralee
Sliab Moduirn: the Mourne Range, in the County Monaghan, partly in Cavan and partly in Meath
Sruthair Finnlethe: a river west of Athlone
Sualtaim (or, Sualtach) Sidech: the human father of Cuchulain
Suide Lagen: Mount Leinster, in the County Wexford