pelvic girdle

:  a bony or cartilaginous arch that supports the hind limbs of a vertebrate, that corresponds to the shoulder girdle of the forelimbs but is usually more rigid and firmly attached to the spinal column, and that consists in lower forms of a single cartilage which is replaced in higher forms including humans by paired hip bones articulating solidly with the sacrum dorsally and with one another at the pubic symphysis