artery [LME] This comes via Latin from Greek artēria, probably from aeirein ‘raise’. Arteries were popularly thought by the ancients (who thought the word was from Greek aēr ‘air’) to be air ducts as they do not contain blood after death. Medieval writers thought they contained an ethereal fluid distinct from that of the veins: this was referred to as spiritual blood or vital spirits. Aorta [M16th] also comes from aeirein. It was used by Hippocrates for the branches of the windpipe, and by Aristotle for the great artery.