counterbore

1 of 2

transitive verb

coun·​ter·​bore

¦kau̇ntə(r)+

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

counterbore

2 of 2

noun

1

: a flat-bottomed enlargement of the mouth of a cylindrical bore

2

: a drill for making a counterbore compare countersink

Word History

Etymology

Transitive verb

counter- + bore

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