The name Asia is ancient, and its origin has been variously explained. The Greeks used it to designate the lands situated to the east of their homeland. It is believed that the name may be derived from the Assyrian word asu, meaning “east.” Another possible explanation is that it was originally a local name given to the plains of Ephesus, which ancient Greeks and Romans extended to refer first to Anatolia (contemporary Asia Minor, which is the western extreme of mainland Asia), and then to the known world east of the Mediterranean Sea. When Western explorers reached South and East Asia in early modern times, they extended that label to the whole of the immense landmass.