COUNTERSINK

counterbore, countersink, countersink bit

(noun) a bit for enlarging the upper part of a hole

countersink

(noun) a hole (usually in wood) with the top part enlarged so that a screw or bolt will fit into it and lie below the surface

set, countersink

(verb) insert (a nail or screw below the surface, as into a countersink)

Source: WordNet® 3.1


Etymology

Noun

countersink (plural countersinks)

a cylindrical recess, typically machined around a hole to admit a screw so that it sits flush with a surface.

Verb

countersink (third-person singular simple present countersinks, present participle countersinking, simple past countersank, past participle countersunk)

(transitive) To create such a conical recess.

(transitive) To cause to sink even with or below the surface.

Source: Wiktionary


Coun"ter*sink` (koun"tr-sk`; 277), v. t. [imp. & p. p. Countersunk (- s; p. pr. & vb. n. Countersinking.]

1. To chamfer or form a depression around the top of (a hole in wood, metal, etc.) for the reception of the head of a screw or bolt below the surface, either wholly or in part; as, to countersink a hole for a screw.

2. To cause to sink even with or below the surface; as, to countersink a screw or bolt into woodwork.

Coun"ter*sink`, n.

1. An enlargement of the upper part of a hole, forming a cavity or depression for receiving the head of a screw or bolt.

Note: In the United States a flaring cavity formed by chamfering the edges of a round hole is called a countersink, while a cylindrical flat-bottomed enlargement of the mouth of the hole is usually called a conterbore.

2. A drill or cutting tool for countersinking holes.

Source: Webster’s Unabridged Dictionary 1913 Edition



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Word of the Day

16 April 2025

RACY

(adjective) marked by richness and fullness of flavor; “a rich ruby port”; “full-bodied wines”; “a robust claret”; “the robust flavor of fresh-brewed coffee”


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According to Guinness World Records, the largest collection of coffee pots belongs to Robert Dahl (Germany) and consists of 27,390 coffee pots as of 2 November 2012, in Rövershagen, Germany.

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