plural of drilling rig

present participle of drill down

Used other than figuratively or idiomatically: see drilling, rig. / An oil rig.

The process of boring a hole deep into the ground for the purpose of extracting a natural resource, such as groundwater, brine, natural gas or crude oil.

A technique for boring holes by means of tools attached to a rope and alternately lifted and lowered.

present participle of match drill

(chiefly of a screw) self-tapping with a drill point

A fluid used to aid the drilling of boreholes, serving to provide hydrostatic pressure, to keep the drill bit cool and clean, and to suspend the drill cuttings.

plural of drilling fluid

(construction) A fastener that taps and drills its own hole during application.