Mining and Geology. Bed-rock: see quots.

the top of the stratum of solid stone or bed-rock beneath the loose or soft superficial deposit; also = stone-heading n.

Chiefly Agriculture. The surface or upper stratum of rock underlying the subsoil.

A bed of rock; a rocky floor, bottom, or base; (in early use) spec. solid rock underlying loose deposits such as soil or alluvium; bedrock.

A rocky underlying surface; bedrock.

The upper surface of bedrock; bedrock.

The solid rock underlying alluvial and other superficial formations; also figurative bottom, lowest level.

Mining (originally Australian). In later use chiefly South African. Unproductive bedrock surrounding gold- or diamond-bearing materials; gangue…