khwan

or khuan

Term found in various of the Thai languages denoting the ‘vital essence’ of a human being, rice plant, or certain animals (such as buffaloes and elephants). Known in Burmese as leikpya, and in Khmer as pralu'n, this ‘vital essence’ is thought to exist in 32 parts of the human body according to the Thai belief, and in nineteen parts according to the Khmer. In practice, however, it is thought of as a unity, and as the spirit that must be within the body of the human being, the rice plant, or the animal if it is not to wither and die, or suffer misfortune. Periodic rituals are performed to secure the khwan to the body, especially following any sudden change in status or place of residence. At death the khwan ceases to exist and a new khwan is formed at conception. Since the khwan is impermanent, and is not understood as an ātman or eternal soul, it poses no direct conflict to the Buddhist teachings of not self (anātman).

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