ovulation /ov′yəlā″shən/ [L, ovum + atio, process] , expulsion of an ovum from the ovary on spontaneous rupture of a mature follicle as a result of cyclic ovarian and pituitary endocrine function. It usually occurs on or about the eleventh to the fourteenth day before the next menstrual period and may cause brief, sharp lower abdominal pain on the side of the ovulating ovary. See also oogenesis. −ovulate, v.
