cosmology. Buddhism inherited much of its traditional cosmology from common Indian lore, and in certain basic respects is consistent with the concepts of modern science, particularly in conceiving the universe to be vastly greater in space and time than it was envisaged to be in the West. The world (loka) in its broadest sense includes the whole cosmos, but within this there are smaller units knows as ‘world-systems’ (lokadhātu), which correspond roughly to solar systems. Such a unit consists of the sun and moon, Mt. Meru, four continents, four oceans, the four great Kings (lokapāla, caturmahārāja), and the sevenfold heavenly spheres. One thousand of these units together forms a ‘small world system’, and the ‘medium’ and ‘large’ systems are each one thousand times greater than the one below. These larger world systems correspond roughly to the modern concept of a galaxy. The cosmos is believed to be infinite in space and also in time, although it passes through immense cycles of evolution and decline. In the post-canonical period of Pāli literature, the term lokadhātu is replaced by cakkavāḷa (Sanskrit, cakravāla), and more elaborate details are added to the traditional accounts. Cosmologies among Buddhists outside India tend to be based on the Indian model, although local cultural influences often modify the original blueprint.

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)