Pelvis
the lower portion of the great abdominal cavity, bounded by the abdomen above, the perineum below, the peritoneum, muscles, and fascia in front, below, and at the side; and the sacral plexus of nerves and the sacrum behind.
It contains the bladder, prostate gland, vesiculæ seminales, and rectum. It is composed of the two ossa innominata, the sacrum and the coccyx. There are marked differences in the male and female pelvis; that of the male is the stronger, with a deeper and much narrower cavity; that of the female is much shallower and more widely expanded.
PEMBROKE COLLEGE