（trisa^hasra-maha^sa^hasra-loka-dha^tu）. One billion worlds， constituting the domain of the Buddha. A world consists of the world of desire and the first heaven of the world of form. One thousand times one thousand times one thousand makes one billion. Commonly abbreviated as sanqianshijie 三千世界. It is a way of describing the vastness and interwovenness of the universe in ancient Indian cosmology.