sacrum [ˈsekrəm, ˈsækrəm]

例句:

• The five vertebrae next to the lumber vertebrae are fused together to form the sacrum.
  在腰椎下是五个椎骨融合在一起形成的骶骨.
  
• On the pelvic surface of the sacrum are four slight ridges.
  在骶骨的骨盆里有四个小的脊.
  
• At the caudal end of the sacrum the roof of the vertebral canal is commonly deficient.
  在骶管末端,椎管往往缺损.
  
• Your sacrum forms the back wall of your pelvis.
  来自BBC