Hérodotosz korában tehát az Ázsia megjelölés elsősorban Kis-Ázsiára vonatkozott, másodsorban a tágabb értelemben vett Szíriára és a Folyamköz térségére (Mezopotámia fogalma is egyébként a hellén forrásokban az évszázadok során nagy változásokon ment át).
Több etimológiai magyarázat lehetséges rá. Vannak, akik a lovat jelentő lúvi au- szóból magyarázzák. Mások hettita vagy akkád eredetűnek tartják:
The word Asia originated from the Greek word "Aσία", first attributed to Herodotus (about 440 B.C.) in reference to Anatolia or, for the purposes of describing the Persian Wars, to the Persian Empire, in contrast to Greece and Egypt. Herodotus comments that he is puzzled as to why three women's names are used to describe one enormous and substantial land mass (Europa, Asia, and Libya, referring to Africa), stating that most Greeks assumed that Asia was named after the wife of Prometheus but that the Lydians say it was named after Asias, son of Cotys who passed the name on to a tribe in Sardis.
Even before Herodotus, Homer knew of a Trojan ally named Asios and elsewhere he describes a marsh as ασιος (Iliad 2, 461). The Greek language term may be derived from Assuwa, a 14th century BCE confederation of states in Western Anatolia. Hittite assu- "good" is probably an element in that name.
Alternatively, the etymology of the term may be from the Akkadian word (w)aşû(m), which means "to go outside" or "to ascend", referring to the direction of the sun at sunrise in the Middle East, and also likely connected with the Phoenician word asa meaning east. This may be contrasted to a similar etymology proposed for Europe, as being from Akkadian erēbu(m) "to enter" or "set" (of the sun). However, this etymology is considered doubtful, because it does not explain how the term "Asia" first came to be associated with Anatolia, which is west of the Semitic-speaking areas, unless they refer to the viewpoint of a Phoenician sailor sailing through the straits between the Mediterranean Sea and the Black Sea.
