countersink

Definitions

Cars & Driving

  • verb to enlarge the part of a hole on the surface of the material so that a conical recess is formed to take the correspondingly shaped head of a screw, which will then be flush with the surface

Construction

  • A conical depression cut to receive the head of a flat-head bolt or screw for driving it flush with thesurrounding surface.
  • A bit used to cut a conical depression.
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