WordReference Random House Unabridged Dictionary of American English © 2020
foot•wall (fŏŏt′wôl′),USA pronunciation n.
- Miningthe top of the rock stratum underlying a vein or bed of ore. Cf. hanging wall (def. 1).
- Geologya mass of rock lying beneath a fault plane.
- foot + wall 1640–50
'footwall' also found in these entries: