countersink

名词 countersink:

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
   同义词：counterbore, countersink bit

动词 countersink:

1. insert (a nail or screw below the surface, as into a countersink)
   同义词：set

coun.ter.sink

n.Abbr. csk.（名词）缩写 csk.
A hole with the top part enlarged so that the head of a screw or bolt will lie flush with or below the surface.
埋头孔：顶部扩大的孔，为使钻或螺栓的头与地面相平或在地面以下
A tool for making such a hole.
埋关钻：制造这种孔的工具
v.tr.（及物动词）
coun.ter.sunk[-sôngk.] coun.ter.sink.ing,coun.ter.sinks
To make a countersink on or in.
在…上或…内造埋头孔
To drive (a screw or bolt) into a countersink.
将钻或螺栓置入埋头孔