DIACRII, in antiquity, was the name of a party or faction at Athens.—That city, we read, was divided into two parties: the one favourers of an oligarchy, who would only have a few persons employed in the government; the other consisted of such as were for a democratical or popular government, wherein the whole people should have a share. The first were called diacrii, and the latter pediuci; the latter inhabiting the lower, and the former the ακρον, or upper quarter or part of the city.—The laws of Solon imported, that Pisistratus should be chief of the diacrii; though the scholiast on Aristophanes's comedy The Wasps, affirms, that Pandion distributed the quarter of the diacrii among his sons, and put Lycus at their head.
DIADELPHIA (δις, "twice," and αδελφες, "a brother"), the 17th class in the sexual system, comprehending those plants which bear hermaphrodite flowers with two sets of united stamens; but this circumstance must not be absolutely depended on. They are the papilionacei of Tournefort, the irregulares tetrapetali of Rivinus, and the leguminosae of Ray. See BOTANY Index.