Definition of: vein

(vān) noun
1. Anat. One of the muscular tubular vessels that convey blood to the heart; loosely, any blood vessel. ♦ Collateral adjective: venal.
2. Entomol. One of the radiating supports of an insect's wing; a rib or nerve.
3. Bot. One of the slender vascular bundles that form the framework of a leaf.
4. Geol. The filling of a fissure or fault in a rock, particularly if deposited by aqueous solutions.
5. A lode.
6. A bed or shoot of ore parallel with the fault.
7. A long, irregular, colored streak, as in wood, marble, etc.
8. A distinctive trait; a specific tendency or disposition.
9. A temporary state of mind; humor; mood.
10. A cavity; cleft; fissure.
11. A crevice or natural channel through which water trickles.
—v.t.
1. To furnish or fill with veins.
2. To streak or ornament with veins.
3. To extend over or throughout as veins. ♦ Homophones: vain, vane. [<OF veine <L vena blood vessel]
—vein′less adjective
—vein′y adjective