Countersunk

['kaʊntɚsʌŋk]

解释:

(imp. & p. p.) of Countersink

(p. p. & a.) Chamfered at the top; -- said of a hole.

(p. p. & a.) Sunk into a chamfer; as, a countersunk bolt.

(p. p. & a.) Beveled on the lower side, so as to fit a chamfered countersink; as, a countersunk nailhead.

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