v.tr. (past and past part. -sunk) 1 enlarge and bevel (the rim of a hole) so that a screw or bolt can be inserted flush with the surface. 2 sink (a screw etc.) in such a hole.
COUNTERSINK
Meaning of COUNTERSINK in English
Concise Oxford English dictionary. Краткий оксфордский словарь английского языка. 2012