DICT.TW Dictionary Taiwan

 coun·ter·sink /ˈkaʊntɚ/
 (vt.)鑽孔裝埋,打埋頭孔于皿錐,埋頭孔,暗釘眼

 Coun·ter·sink v. t. [imp. & p. p.  Countersunk 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.
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 countersink
      n 1: 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
      2: a bit for enlarging the upper part of a hole [syn: counterbore,
          countersink bit]
      v : insert (a nail or screw below the surface, as into a
          countersink) [syn: set]
      [also: countersunk, countersank]