Memory medical terminology word rootVersión en línea to know more about root words in skeletal system por mohamed said Relating to the lumbar region of the spine -petr- Sacrum Cranium -sacr- -crani- Relating to the petrous portion of the temporal bone -rachi- -lumb- Vertebral spine, vertebral column Sternum, breastbone -cost- -pelv/i- Ribs -clavic- / -clavicul- Pelvis, pelvic bone -spondyl- / - vertebr- -stern- Vertebra, spine, vertebral column Clavicle, collarbone