'mother lode' definitions:

Definition of 'mother lode'

(from WordNet)
noun
The main vein of ore in a deposit [syn: mother lode, champion lode]

Definition of 'mother lode'

From: GCIDE
  • Lode \Lode\ (l[=o]d), n. [AS. l[=a]d way, journey, fr. l[imac][eth]an to go. See Lead to guide, and cf. Load a burden.]
  • 1. A water course or way; a reach of water. [1913 Webster]
  • Down that long, dark lode . . . he and his brother skated home in triumph. --C. Kingsley. [1913 Webster]
  • 2. (Mining) A body of ore visibly separated from adjacent rock. [PJC]
  • 3. Especially: (Mining) Any regular vein or course of valuable mineral, whether metallic or not. [1913 Webster]
  • 4. Hence: A concentrated supply or source of something valuable. [PJC]
  • 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. [PJC]