[ floh-jis-ton, -tuh n ]
/ floʊˈdʒɪs tɒn, -tən /


a nonexistent chemical that, prior to the discovery of oxygen, was thought to be released during combustion.


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Origin of phlogiston

1720–30; < New Latin: inflammability, noun use of Greek phlogistón, neuter of phlogistós inflammable, burnt up; see phlogistic Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for phlogiston

British Dictionary definitions for phlogiston

/ (flɒˈdʒɪstɒn, -tən) /


chem a hypothetical substance formerly thought to be present in all combustible materials and to be released during burning

Word Origin for phlogiston

C18: via New Latin from Greek, from phlogizein to set alight; related to phlegein to burn
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

Scientific definitions for phlogiston

[ flō-jĭstən ]

A hypothetical colorless, odorless, weightless substance once believed to be the combustible part of all flammable substances and to be given off as flame during burning. In the 18th century, Antoine Lavoisier proved that phlogiston does not exist. See Note at Lavoisier.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.