A vessel in animal bodies, which receives the blood from the extreme arteries, and returns it to the heart. The veins may be arranged in three divisions. 1. Those that commence from the capillaries all over the body, and return the blood to the heart. 2. The pulmonary veins. 3. The veins connected with the vena portarum, in which the blood that has circulated through the organs of digestion, is conveyed to the liver.

In plants, a tube or an assemblage of tubes, through which the sap is transmitted along the leaves. The term is more properly applied to the finer and more complex ramifications, which interbranch with each other like net-work; the larger and more direct assemblages of vessels being called ribs and nerves. Veins are also found in the calyx and corol of flowers. The vessels which branch or variously divide over the surface of leaves are called veins.

In geology, a fissure in rocks or strata, filled with a particular substance. Thus metallic veins intersect rocks or strata of other substances. Metalliferous veins have been traced in the earth for miles; some in South America are said to have been traced eighty miles. Many species of stones, as granite, porphyryare often found in veins.

A streak or wave of different color, appearing in wood, marble, and other stones; variegation.

A cavity or fissure in the earth or in other substance.

Tendency or turn of mind; a particular disposition or cast of genius; as a rich vein of wit or humor; a satirical vein . Invoke the muses, and improve my vein.

Current. He can open a vein of true and noble thinking.

Humor; particular temper.

Strain; quality; as my usual vein.