SINNA, SENNA, or SINENDRIJ, a town of Persia, in the province of Irak-Ajemi, 285 miles W.S.W. of Teheran. It has a somewhat imposing appearance on account of a palace standing on a hill, and surrounded by several other substantial houses. In the vicinity there are extensive public gardens. The town contains from 4000 to 5000 families.