veinn.[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. (Zol.) 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.(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 associations, thoughts, emotions, or the like; a current; a course; as, reasoning in the same vein.()He can open a vein of true and noble thinking. (Swift.)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. (Bacon.)Invoke the Muses, and improve my vein. (Waller.)v. t. To form or mark with veins; to fill or cover with veins.(Tennyson.)