labia majora /lā″bē·ə məˈjôrə/ sing. labium majus, two long lips of skin, one on each side of the vaginal orifice outside the labia minora. They extend from the anterior labial commissure to the posterior labial commissure and form the lateral boundaries of the pudendal cleft. Each labium contains areolar tissue, fat, and a thin layer of nonstriated muscle. In some women the outer surface of each lip may be covered with coarse pubic hair. The embryonic derivations of the labia majora and the scrotum are homologous.
