from
The Collaborative International Dictionary of English v.0.48
Jigging \Jig"ging\, n. (Mining)
The act or using a jig; the act of separating ore with a
jigger, or wire-bottomed sieve, which is moved up and down in
water.
[1913 Webster]
{Jigging machine}.
(a) (Mining) A machine for separating ore by the process of
jigging.
(b) (Metal Working) A machine with a rotary milling cutter
and a template by which the action of the cutter is
guided or limited; -- used for forming the profile of an
irregularly shaped piece; a profiling machine.
[1913 Webster]