Kilmacthomas, a post-town, partly in the parish of Ballylaneen, but chiefly in that of Rossmire, barony of Decies without Drum, union and county of Waterford, and province of Munster, 12 miles (W.S.W.) from Waterford, and 87¾ (S.W.) from Dublin, on the road from Cork to Waterford: containing 1197 inhabitants, and 214 houses. The town is situated on a steep hill, at the foot of which flows the small river Mahon; there is a good stone bridge. It has a dispensary, and is the head-quarters of the constabulary police for the county: petty sessions are held here, or at Stradbally, on alternate Tuesdays, and fairs are held on Feb.2nd, March 17th, May 12th, Aug 12th, Sept 29th,and Dec 6th and 21st. A castle existed at this place, which was taken by Sir Charles Vavasour in 1643; it belonged to the Poer family, who are still the chief owners of property in the neighbourhood.