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