Answer:

knurl

Answer	Crossword Clue
KNURL	Ridge on a thumbscrew
KNURL	Thumbscrew ridge
KNURL	Small knob

KNURL	Small protuberance
KNURL	Coin-edge ridge
KNURL	Tree knot
KNURL	Make ridges on
KNURL	Button ridge
KNURL	Knob.
KNURL	Small ridge, as on a thumbscrew.
KNURL	Ridge on the edge of a coin.

KNURL	Ridge on a coin.
KNURL	Protuberance
KNURL	Small ridge on the edge of a button or dial
KNURL	Small projecting ridge
KNURL	Bit of metal texturing