DIEST, a town of Belgium, province of South Brabant, and capital of a cognominal canton, is situated on the Demer, 28 miles E. by N. of Brussels. Pop. (1851) 8335. It has manufactures of woollens, hosiery, &c., and some extensive breweries. It was taken from the French by Marlborough in 1705, and retaken the same year.