noun

• (anatomy) Any of the muscular- and elastic-walled blood vessels forming part of the circulation system by which blood is conveyed away from the heart regardless of its oxygenation status; see pulmonary artery.
  "As we age, the major arteries of our bodies frequently become thickened with plaque, a fatty material with an oatmeal-like consistency that builds up along the inner lining of blood vessels. The reason plaque forms isn’t entirely known, but it seems to be related to high levels of cholesterol inducing an inflammatory response, which can also attract and trap more cellular debris over time."
• (transport) A major transit corridor in a system of roads, rivers, or railway lines.
  "But the importance of the railways as main arteries of the national economy remains undimmed, just as their fascination for the railway enthusiast is surely undiminished."