NUN, NON, or NOMI, a river of the Chinese Empire, rises in Manchouria, flows generally southwards, forming part of the boundary between Manchouria and Mongolia, and falls into the Songari, an affluent of the Amur. Its length is about 600 miles, and its chief tributaries are the Hoojur, Noomin, Yalo, Tchola, and Toro.