Vein, v. t. [imp. & p. p. Veined (?); p. pr. & vb. n. Veining.] To form or mark with veins; to fill or cover with veins. Tennyson.

Vein (?), n. [OE. veine, F. veine, L. vena.]

1. (Anat.) One of the vessels which carry blood, either venous or arterial, to the heart. See Artery, 2.

2. (Bot.) One of the similar branches of the framework of a leaf.

3. (Zoöl.) One of the ribs or nervures of the wings of insects. See Venation.

4. (Geol. or Mining) A narrow mass of rock intersecting other rocks, and filling inclined or vertical fissures not corresponding with the stratification; a lode; a dike; -- often limited, in the language of miners, to a mineral vein or lode, that is, to a vein which contains useful minerals or ores.

5. A fissure, cleft, or cavity, as in the earth or other substance. "Down to the veins of earth." Milton.

Let the glass of the prisms be free from veins.
Sir I. Newton.

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

7. A train of association, thoughts, emotions, or the like; a current; a course.

He can open a vein of true and noble thinking.

8. Peculiar temper or temperament; tendency or turn of mind; a particular disposition or cast of genius; humor; strain; quality; also, manner of speech or action; as, a rich vein of humor; a satirical vein. Shak.

Certain discoursing wits which are of the same veins.

Invoke the Muses, and improve my vein.