- Used other than as an idiom: see drill, rig.
(Can we date this quote?), Iqtidar H. Siddiquiyear=1979, Irrigation canals: planning, design, construction, and maintenance:
- In sandy strata, 7 to 9 inches diameter holes are drilled with a percussion type drill rig.
2001, William A. Hustrulid, Richard L. Bullock, Underground Mining Methods, page 224:
- An oil rig.