BAILLEUR, an ancient town of France, in the department of Nord, near the Belgian frontier, situated on a rising ground to the north of the River Lys. It was formerly a place of great strength, and is now a busy industrial tow n, with manufactures of lace, thread, black soap, pottery, woollen stuffs and ribbons, brandy, leather, and cheese. Population, 12,896. Lat. 50° 45' N., long. 2° 44' E.