working substance


: a usually fluid substance that through changes of temperature, volume, and pressure is the means of carrying out thermodynamic processes or cycles (as in a heat engine)

Word History

First Known Use

1855, in the meaning defined above

Time Traveler
The first known use of working substance was in 1855

Dictionary Entries Near working substance

Cite this Entry

“Working substance.” Dictionary, Merriam-Webster, Accessed 11 Dec. 2023.

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