En"tro*py (?), n. [Gr. ? a turning
in; ? in + ? a turn, fr. ? to turn.] (Thermodynamics)
A certain property of a body, expressed as a measurable
quantity, such that when there is no communication of heat the
quantity remains constant, but when heat enters or leaves the body
the quantity increases or diminishes. If a small amount, h, of
heat enters the body when its temperature is t in the
thermodynamic scale the entropy of the body is increased by h ?
t. The entropy is regarded as measured from some standard
temperature and pressure. Sometimes called the thermodynamic
function.
The entropy of the universe tends towards a
maximum.
Clausius.