entropy

entropy /en·tro·py/ (en´tro-pe)

1. the measure of that part of the heat or energy of a system not available to perform work; it increases in all natural (spontaneous and irreversible) processes. Symbol S.

2. the tendency of any system to move toward randomness or disorder.

3. diminished capacity for spontaneous change.

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en·tro·py (ntr-p)

n.

1. 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.

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en·tropic (n-trpk, -trpk) adj.

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entropy

[en′trəpē]

Etymology: Gk, en + tropos, a turning

the tendency of a system to change from a state of order to a state of disorder, expressed in physics as a measure of the part of the energy in a thermodynamic system that is not available to perform work. According to the principles of evolution, living organisms tend to go from a state of disorder to a state of order in their development and thus appear to reverse entropy. However, maintaining a living system requires the expenditure of energy, leaving less energy available for work, with the result that the entropy of the system and its surroundings increases.

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entropy (enˑ·tr·pē),

n the propensity of matter and energy in a closed system to degrade into an equilibrium of uniform inertness and disorder. The apparent suspension of entropy in animate systems is used to support the philosophy of vitalism.

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entropy

1. in thermodynamics, a measure of the part of the internal energy of a system that is unavailable to do work. In any spontaneous process, such as the flow of heat from a hot region to a cold region, entropy always increases.

2. in information theory, the negative of information, a measure of the disorder or randomness in a physical system. The theory of statistical mechanics proves that this concept is equivalent to entropy as defined in thermodynamics.