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equation of state

noun Physics.

an equation relating the temperature, pressure, and volume of a given thermodynamic system.
Also called characteristic equation.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for equation of state

equation of state

noun

any equation that expresses the relationship between the temperature, pressure, and volume of a substance
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012