lode

Từ điển American Heritage Dictionary 4th

lode (lōd)n.
1.
a. The metalliferous ore that fills a fissure in a rock formation.
b. A vein of mineral ore deposited between clearly demarcated layers of rock. Also called lead¹.
2. A rich source or supply. [Middle English, way, load, from Old English lād, way. See leit- in Indo-European Roots.]