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1. (communication theory) a numerical measure of the uncertainty of an outcome
   - information, selective information
    
2. (thermodynamics) a thermodynamic quantity representing the amount of energy in a system that is no longer available for doing mechanical work
   "entropy increases as matter and energy in the universe degrade to an ultimate state of inert uniformity";
   - randomness, S

Derived forms: entropies

Type of: information measure, physical property

Encyclopedia: Entropy