entropi fu'ivla

x1 (amount) is the entropy of system x2 under conditions/in macrostate x3, where the entropy is of type/calculated via formula x4.

Any type of entropy (specified by x4, tanru, "pe", etc.) is allowed, not just Boltzmann entropy (= ".entropi foi'e pe la .boltsman."); Boltzmann entropy should be named as such; the entropy need not be logarithmic. x2 must be a system in the physical sense. See also: boltsemaku, ciste, kalte, cunso, zildatni.

In notes:

x1 is the action (physics quantity) of system x2 during the course of evolution/history/over path/within spacetime region x3 under conditions x4