— synsacral , adj.
/sin sak"reuhm, -say"kreuhm/ , n. , pl. synsacra /-sak"reuh, -say"kreuh/ . Ornith.
a dorsal ridge of bone in the pelvic region of birds, formed by the fusion of certain thoracic, lumbar, sacral, and caudal vertebrae.
[ 1900-05; SYN- + SACRUM ]