counterboring

/K AW0 N T ER0 B ER0 IH0 NG/
verb
  1. 1

    To create such a cylindrical recess.

noun
  1. 1

    A counterbore. (cylindrical recess)

Source: https://en.wiktionary.org/wiki/counterbore, https://en.wiktionary.org/wiki/counterboring