uterus - a hollow muscular organ in the pelvic cavity of females; contains the developing fetusventer - the womb; "`in venter' is legal terminology for `conceived but not yet born'" uterine cavity - the space inside the uterus between the cervical canal and the Fallopian tubes endometrium - (pregnancy) the mucous membrane that lines the uterus; thickens under hormonal control and (if pregnancy does not occur) is shed in menstruation; if pregnancy occurs it is shed along with the placenta at parturition myometrium - the smooth muscle forming the wall of the uterus placenta - the vascular structure in the uterus of most mammals providing oxygen and nutrients for and transferring wastes from the developing fetus |