Synonyms for Vein (same or very similar meaning)
WordNet sense 1 (any of the vascular bundles or ribs that form the branching framework of conducting and supporting tissues in a leaf or other plant organ):
nervure
WordNet sense 2 (a layer of ore between layers of rock):
mineral vein
WordNet sense 3 (a blood vessel that carries blood from the capillaries toward the heart):
vena, venous blood vessel
From the ODE community, based on WordNet
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