entropy

noun
en·​tro·​py | \ ˈen-trə-pē How to pronounce entropy (audio) \
plural entropies

Definition of entropy

1 thermodynamics : a measure of the unavailable energy in a closed thermodynamic system that is also usually considered to be a measure of the system's disorder, that is a property of the system's state, and that varies directly with any reversible change in heat in the system and inversely with the temperature of the system broadly : the degree of disorder or uncertainty in a system
2a : the degradation of the matter and energy in the universe to an ultimate state of inert uniformity Entropy is the general trend of the universe toward death and disorder.— James R. Newman
b : a process of degradation or running down or a trend to disorder The deterioration of copy editing and proof-reading, incidentally, is a token of the cultural entropy that has overtaken us in the postwar years.— John Simon
4 statistical mechanics : a factor or quantity that is a function of the physical state of a mechanical system and is equal to the logarithm of the probability for the occurrence of the particular molecular arrangement in that state
5 communication theory : a measure of the efficiency of a system (such as a code or a language) in transmitting information, being equal to the logarithm of the number of different messages that can be sent by selection from the same set of symbols and thus indicating the degree of initial uncertainty that can be resolved by any one message

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Other Words from entropy

entropic \ en-​ˈtrō-​pik How to pronounce entropic (audio) , -​ˈträ-​pik \ adjective
entropically \ en-​ˈtrō-​pi-​k(ə-​)lē How to pronounce entropically (audio) , -​ˈträ-​ \ adverb

Did You Know?

With its Greek prefix en-, meaning "within", and the trop- root here meaning "change", entropy basically means "change within (a closed system)". The closed system we usually think of when speaking of entropy (especially if we're not physicists) is the entire universe. But entropy applies to closed systems of any size. Entropy is seen when the ice in a glass of water in a warm room melts—that is, as the temperature of everything in the room evens out. In a slightly different type of entropy, a drop of food coloring in that glass of water soon spreads out evenly. However, when a nonphysicist uses the word, he or she is usually trying to describe a large-scale collapse.

Examples of entropy in a Sentence

Recent Examples on the Web

Then calculate the entropy using the formula (14 + 4u – 2b – t)/42. Quanta Magazine, "Solution: ‘Time Through an LCD Display’," 30 Sep. 2016 Seekers of immortality are saddled with the body, the physical brain, the fact of entropy. Josh Wilbur, WIRED, "You Could Live Forever With This Sci-Fi Time Hack," 4 June 2019 The speed with which the hotel in Lab—which began as a prison, the ultimate symbol of modern efforts at social control—deteriorates in the absence of human oversight suggests the power of entropy to tear apart any human endeavor. Christopher Beha, Harper's magazine, "Mallo My!," 10 Mar. 2019 There's a certain satisfaction fighting against entropy in such a simple, straightforward way—taking a disordered world and converting it into a clean, simple nothingness. Kyle Orland, Ars Technica, "Donut County lets you become one with nothingness," 27 Aug. 2018 If the atoms were not super-cooled, rearranging them would have little effect on the system's overall entropy. Jennifer Ouellette, Ars Technica, "Penn State scientists build quantum version of Maxwell’s demon," 12 Sep. 2018 The place had the slightest touch of Grey Gardens to it, though without the unapologetic embrace of entropy. James Mcauley, Town & Country, "The Tragic, Fascinating History of Santo Sospir," 13 Aug. 2018 Smithson was a big believer in entropy and its laws that energy is more easily lost then gained. Anne Slowey, Condé Nast Traveler, "Fear and Self-Loathing in the American Southwest," 25 July 2018 The underlying law of our universe is entropy, or constant descent into disorder. WSJ, "Modern Heraclitus: Trump’s Genius for Chaos," 1 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'entropy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of entropy

1867, in the meaning defined at sense 1

History and Etymology for entropy

International Scientific Vocabulary en- entry 2 + Greek tropē change, literally, turn, from trepein to turn

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Dictionary Entries near entropy

entrepreneuse

entresol

entropion

entropy

entruck

entrust

entry

Statistics for entropy

Last Updated

17 Jul 2019

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Time Traveler for entropy

The first known use of entropy was in 1867

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More Definitions for entropy

entropy

noun
en·​tro·​py | \ ˈen-trə-pē How to pronounce entropy (audio) \
plural entropies

Medical Definition of entropy

: a measure of the unavailable energy in a closed thermodynamic system that is also usually considered to be a measure of the system's disorder and that is a property of the system's state and is related to it in such a manner that a reversible change in heat in the system produces a change in the measure which varies directly with the heat change and inversely with the absolute temperature at which the change takes place broadly : the degree of disorder or uncertainty in a system

Other Words from entropy

entropic \ en-​ˈtrōp-​ik How to pronounce entropic (audio) , -​ˈträp-​ How to pronounce entropic (audio) \ adjective
entropically \ -​i-​k(ə-​)lē How to pronounce entropically (audio) \ adverb

More from Merriam-Webster on entropy

Britannica English: Translation of entropy for Arabic Speakers

Britannica.com: Encyclopedia article about entropy

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