1 of 2

transitive verb

: to form a counterbore in : enlarge (part of a hole) by means of a counterbore


2 of 2


: a flat-bottomed enlargement of the mouth of a cylindrical bore
: a drill for making a counterbore compare countersink

Word History


Transitive verb

counter- + bore

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Dictionary Entries Near counterbore

Cite this Entry

“Counterbore.” Dictionary, Merriam-Webster, Accessed 7 Dec. 2023.

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