What is "xaltocan"

Xaltocan was a pre-Columbian city-state and island in the Valley of Mexico, located in the center of Lake Xaltocan, part of an interconnected shallow lake system which included Lake Texcoco. The site was originally settled by the Otomi people, but following a war in the late fourteenth century where the Otomi were defeated by an alliance of Tepanecs and Mexica the Otomi were driven off the island and relocated to Otumba, Metztitlan and Tlaxcala. The island of Xaltocan was then resettled by Nahuatl speakers. The name can mean either of two things in the Nahuatl language: either 'sandy ground of spiders' or 'where sand sowing'.