vein

Concise Oxford English Dictionary © 2008 Oxford University Press:
vein/veɪn/

▶noun

• 1 any of the tubes forming part of the circulation system by which blood is conveyed from all parts of the body towards the heart.

  ■ (in general use) a blood vessel.

• 2 (in plants) a slender rib running through a leaf, typically dividing or branching, and containing vascular tissue.

  ■ (in insects) a hollow rib forming part of the supporting framework of a wing.

• 3 a streak or stripe of a different colour in wood, marble, cheese, etc.

  ■ a fracture in rock containing a deposit of minerals or ore.

  ■ a source of a specified quality: he has tapped a national vein of anger.

• 4 a distinctive quality, style, or tendency: he closes his article in a humorous vein.

– derivatives
veined adjective,
veining noun,
veinless adjective,
veinlet noun,
vein-like adjective,
veiny adjective.

– origin ME: from OFr. veine, from L. vena.