phlogiston(redirected from Phlogiston theory)
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A hypothetical substance formerly thought to be a volatile constituent of all combustible substances, released as flame in combustion.
(Chemistry) chem a hypothetical substance formerly thought to be present in all combustible materials and to be released during burning
[C18: via New Latin from Greek, from phlogizein to set alight; related to phlegein to burn]
phlo•gis•ton(floʊˈdʒɪs tɒn, -tən)
a nonexistent chemical that, prior to the discovery of oxygen, was thought to be released during combustion.
[1720–30; < New Latin: inflammability, n. use of Greek phlogistón, neuter of phlogistós inflammable, burnt up; see phlogistic]
A 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.
Obsolete Chemistry. a hypothetical ingredient thought to be released during combustion. — phlogistic, adj.See also: Fire