We don't have synonyms for countersank yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are countermand, counterpane and countersink.
(n) :
A conical recess, typically machined at the mouth of a hole to admit a screw (with a matching taper) so that the screw sits flush with a surface.
(v) :
(transitive) To create such a conical recess.
(n) :
The cutter used to cut such a recess. (Also used, at less depth, for edge-breaking/deburring.)
(v) :
(ambitransitive) To cause to sink even with or below the surface.
(n) :
A conical recess, typically machined at the mouth of a hole to admit a screw (with a matching taper) so that the screw sits flush with a surface.
(v) :
(transitive) To create such a conical recess.
(n) :
The cutter used to cut such a recess. (Also used, at less depth, for edge-breaking/deburring.)
(v) :
(ambitransitive) To cause to sink even with or below the surface.