OHRDRUF, a town of Saxe-Coburg-Gotha, in the principality of Gotha, on the Ohra, 8 miles S. of Gotha. It has a castle, a newly-erected town-hall, and several churches and schools. Manufactures of woollen cloth, porcelain, organs, &c., are carried on here; and there are also numerous mills and bleach-works. The trade is considerable in wool, coals, &c. Pop. 4559.