counterbored的翻译，读音

释义：

单词counterbored书写

(counterbore 的过去分词) (用平底扩孔钻)扩孔［锪孔, 镗孔, 镗阶梯孔］, 沉孔, 埋头孔
past participle of counterbore
n a bit for enlarging the upper part of a hole