Entropy is the steady drift of order into disorder. Increasing entropy, the entropy of the system, fight entropy.
In physics it is a measured quantity and the second law says it never decreases in a closed system, which is why heat flows one way and time seems to. The loose use, meaning things falling apart, borrows the idea rather than the mathematics.
1nounentropyThe steady drift of order into disorder.
“As the ice melts and the heat spreads out evenly, the entropy of the system rises.”
entropy is a measure.
Coined in German in 1865 by Rudolf Clausius, on the model of energy, from Greek trope, a turning.
Ancient Greek
τροπή — transformation
German
Entropie
English, today
entropy
Built from
History of + First attested in 1867, as the translation of German Entropie, coined in 1865 by Rudolph Clausius in analogy to Energie (“energy”), replacing the root of Ancient Greek ἔργον (“work”) by Ancient Greek τροπή (“transformation”)).
Etymology from Wiktionary, CC BY-SA