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Glite Dictionary
🛠️ A drill bit 🛠️ To enlarge opening 🕳️ A recessed hole
counterbore

counterbore

8.8
A hole with a wider flat top so a screw head sits below the surface
  • noun
  • /ˈkaʊntərˌbɔr/
  • Specialized
translation icon : contraboceto
  • A counterbore is essential for this type of installation.

Examples

  • The engineer specified a counterbore to ensure the bolt head would not stick out.

  • A proper counterbore is important when assembling furniture with flat surfaces.

  • Before inserting the screw, he made a counterbore so the surface would remain smooth.

  • The technician used a counterbore to ensure the screw sits flush.

  • Make sure to use the right drill bit to create a counterbore for the screw so it sits flush with the wood.

  • The counterbore allows the screw head to be completely hidden within the surface of the table.

  • He measured the depth of the counterbore to ensure the bolt head would not protrude.

Surface Forms

counterbore singular
counterbores plural

Morphology

counterbore = bore (semi-transparent) = counter + bore

Built from 'counter' + 'bore' so learners can guess it's a kind of bore, but the specialized sense 'a recessed hole to accept a screw head' is technical.

Etymology

Counterbore comes from counter 'against' and bore 'to make a hole', and it names the wider, flat-bottomed opening at the top of a hole so a screw or bolt head will sit level with the surface.