noun. A stack or cock, as of grain.

noun. A rick of corn in the straw laid up in a barn.

noun. 3. In coal-mining, a space from which coal has been worked away, and which is more or less filled up with refuse.

noun. That part of a mine from which the mineral has been partially or wholly removed; the waste left in old workings; -- called also gob .

noun. to remove the pillars of mineral matter previously left to support the roof, and replace them with props.

noun. undefined

noun. That part of a mine from which the mineral has been partially or wholly removed; the waste left in old workings.

"But experts said that the preferred theory was that a collapse of the mine's roof in the "goaf" - the void left behind after coal is removed - released methane into the mine."

to work the gob  

gob