1868年，来自德文 Entropie "系统无序的度量"，1865年德国物理学家鲁道夫-克劳修斯(Rudolph Clausius，1822-1888)在他的热力学定律著作中创造了这个词(类比 Energie )，来自希腊文 entropia "转向"，来自 en "在"(见 en- (2))+ trope "一个转折，一个转变"(来自PIE根 *trep- "转折")。这个概念应该是"转化内容"。相关链接： Entropic .
It was not until 1865 that Clausius invented the word entropy as a suitable name for what he had been calling "the transformational content of the body." The new word made it possible to state the second law in the brief but portentous form: "The entropy of the universe tends toward a maximum," but Clausius did not view entropy as the basic concept for understanding that law. He preferred to express the physical meaning of the second law in terms of the concept of disgregation, another word that he coined, a concept that never became part of the accepted structure of thermodynamics. [Martin J. Klein, "The Scientific Style of Josiah Willard Gibbs," in "A Century of Mathematics in America," 1989]