The story
Uncertain. One suggested meaning is "place of Herons" or "place of egrets", but this is not possible under Nahuatl morphology: "place of egrets" is Aztatlan. Other proposed derivations include "place of whiteness" and "at the place in the vicinity of tools", sharing the āz- element of words such as teponāztli, "drum" (from tepontli, "log")
Etymology from Wiktionary, CC BY-SA 4.0.