Third-person singular simple present indicative form of countersink.(verb)
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Use "countersinks" in a sentence
"Seems to me like this would be a whole lot easier with some sort of sticky Velcro solution or something similar instead of having to screw around with the drilling and countersinks and what have you."
"These drilling machines are applied to manufacture single vertical round bores for mountings and countersinks at screw holes for mountings or single dowel bits."
"· Drills, cylindrical and taper reamers, countersinks, triangular scrapers"