accelerant
n. countablen. a substance that makes a fire burn faster or more easily. It is often used to start a fire or to make it spread more quickly.
n. a substance that increases the speed or intensity of a chemical reaction, particularly combustion. Often used in forensic contexts to identify materials used to ignite a fire.
The fire started because someone used an accelerant.
Fire investigators found traces of an accelerant in the basement, suggesting the blaze was not an accident.
While gasoline is a common accelerant, forensic chemists must also test for less volatile substances like alcohol or lighter fluid to determine the fire's origin.
From accelerate + -ant (suffix forming agent nouns from verbs, or forming adjectives with senses of being prone or tending to do the actions of verbs).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Last updated June 4, 2026