inflammable

American  

[in-flam-uh-buhl] / ɪnˈflæm ə bəl /

adjective

1. capable of being set on fire; combustible; flammable.

2. easily aroused or excited, as to passion or anger; irascible.

   an inflammable disposition.

   Synonyms:

   choleric, volatile, fiery

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noun

1. something inflammable.

inflammable British  

/ ɪnˈflæməbəl /

adjective

1. liable to catch fire; flammable

2. readily aroused to anger or passion

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noun

1. something that is liable to catch fire

Commonly Confused

Inflammable and flammable both mean “combustible.” Inflammable is the older by about 200 years. Flammable now has certain technical uses, particularly as a warning on vehicles carrying combustible materials, because of a belief that some might interpret the intensive prefix in- of inflammable as a negative prefix and thus think the word means “noncombustible.” Inflammable is the word more usually used in nontechnical and figurative contexts: The speaker ignited the inflammable emotions of the crowd.

Other Word Forms

• inflammability
  noun
• inflammableness
  noun
• inflammably
  adverb
• noninflammability
  noun
• noninflammable
  adjective
• noninflammableness
  noun
• noninflammably
  adverb
• uninflammability
  noun
• uninflammable
  adjective

Etymology

Origin of inflammable

1595–1605; < Medieval Latin inflammābilis, equivalent to Latin inflammā ( re ) to inflame + -bilis -ble

Explanation

Something that is inflammable can be set on fire easily. You dared not light a match after you accidentally spilled gasoline on yourself because you knew you were inflammable. Inflammable can be a tricky word, since the in- prefix often means "not." But in this case, the in- isn't really a prefix, because the word is built from the verb inflame which means "to set on fire." Some inflammable things might literally go up in flames, but we also use it metaphorically. Someone with a quick temper could be described as "inflammable," and if you fall in love easily, then you have an inflammable heart.

Example Sentences

In 1878, The Washington Post published a brief article under the headline, “The Army Medical Museum a Magazine of Inflammable Material.”

From Washington Post • Nov. 4, 2017

Inflammable gas escapes, which, if ignited, will burn with great brilliancy for many hours, and even for several days, in a favorable state of the atmosphere.

From A New Guide for Emigrants to the West by Peck, John Mason

Inflammable air kills animals as suddenly as fixed air, and, as far as can be perceived, in the same manner, throwing them into convulsions, and thereby occasioning present death.

From Experiments and Observations on Different Kinds of Air by Priestley, Joseph

Inflammable air admitted to alkaline air exhibited no particular appearance.

From Experiments and Observations on Different Kinds of Air by Priestley, Joseph

Inflammable air, however, will not mix with acid or alkaline air.

From Heads of Lectures on a Course of Experimental Philosophy: Particularly Including Chemistry by Priestley, Joseph