Lumbosacral \Lum`bo*sa"cral\, n. [L. lumbus loin + E. sacral.] (Anat.) Of or pertaining to the loins and sacrum; as, the lumbosacral nerve, a branch of one of the lumber nerves which passes over the sacrum.
lumbosacral adj : of or relating to or near the small of the back and the back part of the pelvis between the hips