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

Derived Forms

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

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 air with a mixture of nitrous air burns with a green flame.

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

Inflammable air is procured from all combustible substances by means of heat and water, and from several of the metals, especially iron, zink, and tin, by the vitriolic and marine acids.

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

Inflammable impulse of beauty, The breath of whose ardor is grief; The God, in fulfilment of duty, Hath stamped thee in highest relief!

From The Goddess of Atvatabar Being the history of the discovery of the interior world and conquest of Atvatabar by Bradshaw, William Richard

Inflammable matter must be kept far from fire; whereas matter that is incombustible may, when a necessary cause occurs, safely pass through the midst of the flame.

From The Parables of Our Lord by Arnot, William