Hypertext Webster Gateway: "counterbore"
From Webster's Revised Unabridged Dictionary (1913) (web1913)
Counterbore \Coun"ter*bore`\ (-b?r`), n.
1. A flat-bottomed cylindrical enlargement of the mouth of a
hole, usually of slight depth, as for receiving a
cylindrical screw head.
2. A kind of pin drill with the cutting edge or edges normal
to the axis; -- used for enlarging a hole, or for forming
a flat-bottomed recess at its mouth.
From Webster's Revised Unabridged Dictionary (1913) (web1913)
Counterbore \Coun`ter*bore"\ (koun`t?r-b?r"), v. t.
To form a counterbore in, by boring, turning, or drilling; to
enlarge, as a hole, by means of a counterbore.
From WordNet (r) 1.7 (wn)
counterbore
n : a bit for enlarging the upper part of a hole [syn: {countersink},
{countersink bit}]
Additional Hypertext Webster Gateway Lookup
Gateway by dict@stokkie.net
stock only wrote the gateway and does not have any control over the contents;
see the Webster Gateway FAQ,
and also the Back-end/database links and credits.