DRIMNAGH, or DRIMNA, a parish (formerly), in the barony of UPPERCROSS, county of DUBLIN, and province of LEINSTER, 2 miles (W. S. W.) from Dublin, on the road to Naas and on the Grand Canal. This ancient parish has merged into that of Clondalkin. There is a paper-mill at Lansdowne Valley; and near the Blue Bell is a woollen factory, at which coarse cloths are manufactured. In the direction of Crumlin stands Drimna Castle, formerly the head of a manor, of which the Barnewall family were lords from the time of John to that of Jas. I., and which was a place of some consequence in the reign of Chas. I. It is the property of the Marquess of Lansdowne, and is an irregular pile, occupied, by Mr. E. Cavanagh. The church is in ruins. In the R. C. divisions it is part of the district of Lucan, Palmerstown, and Clondalkin.