1520s, "the business or work of a miner," verbal noun from mine (v.1). From c. 1300 as "the undermining of walls or towers in a military attack." Mining-camp "temporary settlement for mining purposes" is by 1853, in a California context.

c. 1300, minen, "to dig a tunnel under fortifications to overthrow them," from mine (n.1) or from Old French miner "to dig, mine; exterminate," from the French noun. From mid-14c. as "to dig in the earth" (in order to obtain minerals, treasure, etc.). Figurative meaning "ruin or destroy by slow or secret methods" is from mid-14c. Transitive sense of "to extract by mining" is from late 14c. For the sense of "to lay (explosive) mines," see mine (v.2). Related: Mined; mining.

1870, in mining, of ores, from high (adj.) + grade (n.).

1867, originally in mining, with reference to ores, from low (adj.) + grade (n.).

1747, a mining word, from Low German stope "a step," apparently cognate with step (n.). As a verb from 1778, "remove the contents of a vein," literally "to cut in stopes." Related: Stoped; stoping.

1530s, "locality where mining is carried on," verbal noun from dig (v.). Diggings, colloquial for "lodgings, quarters" is by 1838.

1590s, "let out, cause to flow out; draw off (liquid)," by or as by a sluice, from sluice (n.). In gold-mining, "to scour or cleanse by a sluice," by 1859. Related: Sluiced; sluicing.

also pay dirt, "profit, success," 1873, from pay (n.) + dirt (n.); a word from mining, where it was used by 1856 in a literal sense of "gravel or sand containing a sufficient amount of gold to be profitably worked."

1872, originally a term in mining, from stock (n.2) + pile (n.). Extended to general use during World War II. The verb is attested from 1921. Related: Stockpiled; stockpiling.

also prospecter, 1846 in the mining sense of "one who searches for valuable minerals or ores as a preliminary to regular operations;" agent noun from prospect (v.).