Lode

n. [AS. l[=a]d way, journey, fr.l[imac][eth]an to go. See Lead to guide, and cf. Load a burden.]
n, a deposit of valuable ore occurring within definite boundaries separating it from surrounding rocks [syn: load]
A water course or way; a reach of water. Down that long, dark lode . . . he and his brother skated home in triumph.-C. Kingsley.
(Mining) A body of ore visibly separated from adjacent rock. Especially: (Mining) Any regular vein or course of valuable mineral, whether metallic or not.
1. Hence: A concentrated supply or source of something valuable.
2. mother lode a large concentrated source of mineral or other valuable thing, from which lesser sources have been derived; – often used figuratively. The term may have been originally applied to real or imagined large deposits of gold from which smaller granules were washed downstream, there constituting a diluted source of gold, and hinting at the richer source from which they were derived; as, to hit the mother lode.