Wiktionary
longwall
n. (context mining English) A long wall of coal that is mined in a single slice.
Usage examples of "longwall".
She saw Algarin of Longwall, Heremon the Mage, and a few other familiar faces among them.
That was a force seven bump, with its source plumb in the middle of our eastern longwall at 95 level.
Johnny reached the top of his longwall and painted in the last shot holes.