1923, California. Division of Oil and Gas, Summary of Operations; Annual Report of the State Oil and Gas Supervisor, page 83:
Records of closed-in fluid or gas pressure.
1988, Official Gazette of the United States Patent and Trademark Office: Patents, page 1120:
A control arrangement for a heat recovery system comprising: a fluid or gas medium system containing a fluid or gas to be heated; a source of superheated condensible heat exchange medium; a heat recovery system ...
2016, Chaim Gans, A Political Theory for the Jewish People, Oxford University Press (→ISBN), page 45:
As water does not stop being H2O whether it's fluid, congeals into ice, or turns into steam, […]