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