What is "cihai"

The Cihai is a large-scale Chinese dictionary and encyclopedia. The Zhonghua Book Company published the first Cihai edition in 1938, and the Shanghai Lexicographical Publishing House revised editions in 1979, 1989, 1999, and 2009. A standard bibliography of Chinese reference works (Teng and Biggerstaff 1971:134) calls the Cihai an "outstanding dictionary".