before vowels angi-, word-forming element meaning "vessel of the body," now often "covered or enclosed by a seed or blood vessel," from Latinized form of Greek angeion "case, capsule, vessel of the body," diminutive of angos "vessel, jar, vat, vase," which is of unknown origin. Beekes says "Possibly a Mediterranean loanword ..., as kitchen utensils are often borrowed."
They were regarded by the ancients as air ducts because the arteries do not contain blood after death, and 14c.-16c. artery in English also could mean "trachea, windpipe." Medieval writers, based on Galen, generally took them as a separate blood system for the "vital spirits." The word is used in reference to artery-like systems of major rivers from 1805; of railways from 1844.