n. pl. en·tro·pies
1. Symbol S For a closed thermodynamic system, a quantitative measure of the amount of thermal energy not available to do work.
2. A measure of the disorder or randomness in a closed system.
3. A measure of the loss of information in a transmitted message.
4. The tendency for all matter and energy in the universe to evolve toward a state of inert uniformity.
5. Inevitable and steady deterioration of a system or society.
[German Entropie : Greek en-, in; see EN-2 + Greek tropē, transformation; see trep- in the Appendix of Indo-European roots.]
en·tropic (ĕn-trōpĭk, -trŏpĭk) adj.
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