spec. The action or act of boring or excavating downwards in search of coal or ore; (also) the pit or shaft thus formed.

a framework used in mining.

The action of stope, v.

The process of excavating a mine shaft or sump (sump, n. 2a). Also: a small mine shaft (cf. sump, n. 2b). Obsolete.

spec. in Mining (see drift, v. 7). Also attributive.

The sinking of a shaft; also, the shafts of a mine collectively.