Sekirov Dictionary

counterbore

noun 2
verb 1
forms 3

noun2

A cylindrical recess, typically machined at the mouth of a hole to admit a screw (such as a cap screw) so that the screw sits flush with a surface.
The cutter used to cut such a recess. (Also used, at less depth, for spotfacing.)

verb1

To create such a cylindrical recess.

forms

counterbored · counterboring · counterbores

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