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