KILLAGHIN, or KILLAHEN, a parish, in the barony of CLANMAURICE, county of KERRY, and province of MUNSTER, 5½ miles (N.) from Tralee, on the road from Abbeydorney to Cashen-ferry; containing 1098 inhabitants. It comprises 4239 statute acres, of which about one-fourth consists of mountain and bog, and the remainder of arable land of variable quality. The principal residence is Fort William, belonging to the representatives of the late W. Collis, Esq. The parish is in the diocese of Ardfert and Aghadoe: the rectory is impropriate in the Earl of Cork, and the vicarage forms part of the union of Kilflyn, or Ballinacourty; the tithes amount to £126, of which two-thirds are payable to the impropriator, and the remainder to the vicar. In the R. C. divisions it forms part of the union or district of Abbeydorney. The ruins of the old church still remain; and about a mile to the west are those of Ballyrnaquin castle.