countersinking

• vt.countersink的变形

countersink['kauntə,siŋk]

• vt.
  • 钻埋头孔，穿孔；打埋头孔于
  • 将(螺钉等)装入埋头孔
• n.
  • 【机械学】埋头钻，锥口钻
  • 埋头孔，锥口孔
• 变形:

  vt.countersank.countersunk.countersinking