phlo·​gis·​ton | \ flō-ˈji-stən How to pronounce phlogiston (audio) \

Definition of phlogiston

: the hypothetical principle of fire regarded formerly as a material substance

Examples of phlogiston in a Sentence

Recent Examples on the Web Lavoisier didn’t think that Priestley was right about phlogiston, prompting a long-running battle. Kat Eschner, Smithsonian, "The Father of Modern Chemistry Proved Respiration Occurred by Freezing a Guinea Pig," 25 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phlogiston.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of phlogiston

1733, in the meaning defined above

History and Etymology for phlogiston

New Latin, from Greek, neuter of phlogistos inflammable, from phlogizein to set on fire, from phlog-, phlox flame, from phlegein

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The first known use of phlogiston was in 1733

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Cite this Entry

“Phlogiston.” Dictionary, Merriam-Webster, Accessed 30 May. 2020.

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Rhyming Dictionary: Words that rhyme with phlogiston Encyclopedia article about phlogiston

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