knurl

(nûrl)
n.

1. A knob, knot, or other small protuberance.
2. One of a series of small ridges or grooves on the surface or edge of a metal object, such as a thumbscrew, to aid in gripping.

tr.v., knurled, knurl·ing, knurls.
To provide with knurls; mill.

[Probably diminutive of KNUR .]

knurled knurled (nûrld) adj.
knurly knurl'y adj.