The word “countersink” can function as both a noun and a verb.
As a noun, a “countersink” refers to a conical hole cut into a material, such as wood or metal, to allow the head of a screw or bolt to sit flush with or below the surface of the material.
As a verb, “to countersink” means to create such a conical hole in a surface, typically to accommodate the head of a fastener, ensuring a smooth and even surface finish.
In both cases, the purpose of countersinking is to enable a fastener to be embedded in the material, providing a neater appearance and reducing the risk of snagging or damage.
