This pioneering book is the prototype of the etymological thesaurus that has been the goal of the Sino-Tibetan Etymological Dictionary and Thesaurus project (STEDT) since 1987. It presents nearly 170 Proto-Tibeto-Burman etymologies in the semantic area of the reproductive system, along with discussions of possible Chinese cognates. Special attention is paid to patterns of semantic associations between the reproductive system and other areas of the lexicon.