What does accelerant mean?
An accelerant is a substance that speeds up a process, most commonly a flammable material such as petrol, kerosene, or alcohol used to make a fire burn faster and more intensely. The term is central to forensic fire investigation, where analysts test debris for chemical residues to determine whether a blaze was deliberately set — the presence of an unidentified accelerant is often key evidence in arson cases. Beyond its literal use, accelerant has developed a productive figurative sense, describing anything that hastens growth or change: cheap credit can be an accelerant of speculation, and social media an accelerant of rumour. The word derives from the Latin celer, meaning swift, via the verb accelerate. It functions only as a noun, with the standard plural accelerants, and its strong forensic connotations mean it should be used with care in neutral contexts.
nounA substance, typically a flammable liquid such as petrol or kerosene, used to speed up the spread of fire. More broadly, anything that accelerates a process or increases its rate of progress.
- A flammable substance used to hasten the spread of fire, especially in cases of arson.
- Something that speeds up a process, reaction, or development (e.g. in chemistry, business, or biology).
"Fire investigators found traces of an accelerant among the charred remains of the warehouse."
"Investigators determined that petrol had been used as an accelerant to start the blaze."
"Low interest rates acted as an accelerant for the housing boom."
Standard regular plural; commonly used when referring to multiple substances found at a fire scene or several agents of growth.
"Investigators collected samples to test for a range of accelerants."
The word 'accelerant' comes from Latin celer, meaning 'swift' — the same root that gives us 'celerity', and the reason a cheetah's genus name is Acinonyx... well, almost: it's why we say things happen at 'accelerated' speed.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of accelerant
Accelerant entered English in the early 20th century, formed from the verb accelerate, which itself derives from the Latin accelerare ('to hasten'), built on celer, meaning 'swift'. The same Latin root gives English celerity and acceleration. The noun originally described any agent of speeding-up but became strongly associated with fire investigation during the 20th century as forensic science developed techniques for detecting flammable residues.
How accelerant is actually used
The fire-related sense is by far the most common and carries strong associations with arson investigation; using it metaphorically (e.g. for economic growth) is a deliberate, slightly literary extension. The plural 'accelerants' is standard when referring to multiple substances.
Easily confused with accelerant
An accelerator is something that increases speed or rate (such as a pedal or particle accelerator), while an accelerant is specifically a substance that speeds up burning or another process.