from
The Collaborative International Dictionary of English v.0.48
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]