plastron ['plæstrən]

例句:

• Tortoises seem to preferentially put the available calcium in the plastron.
  龟们似乎更喜欢把可用的钙质添加到他们的胸甲中.
  
• Objective : To identify the commercial Chinese medicines turtle shell and tortoise plastron.
  目的: 鉴定鳖甲、龟甲类商品药材.
  
• After the tortoise is anesthetized the bottom of the shell ( called the plastron ) is cleansed thoroughly.
  当乌龟被麻醉后,他的胸 甲 要被彻底清洗干净.
  
• The top part of the shell is the carapace, the underside is the plastron, and the two are connected by the bridge.
  来自BBC
• If so, the plastron would have shielded the turtle's underside from predators approaching from below.
  来自SA