Asia derives from the Ancient Greek "Aoía", which was used as early as 440 B.C. by Herodotus in his Historian years. However, it is likely that the name was in use long before then, although not referring to a whole continent. It's rather originally just the name for land on the east bank of the Aegean (which means Asian) Sea, and then later the Anatolia was soon called another word meaning Asia.
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