What does nonflammable mean?
Nonflammable is an adjective meaning not flammable: incapable of catching fire or burning readily. It is commonly applied to materials, fabrics, chemicals, furnishings, and building components in technical, industrial, and safety contexts. For example, regulations may specify nonflammable storage containers or nonflammable insulation. The word is especially useful because it distinguishes ordinary combustible substances from materials intended to reduce the risk of ignition. It does not necessarily mean completely fireproof; a nonflammable material may still be damaged by intense heat, while fire-resistant describes a different relationship to fire exposure. Although the negative prefix is easy to interpret, nonflammable is sometimes confused with inflammable, which in modern English normally means flammable and therefore has the opposite meaning.
adjectiveNot flammable; incapable of catching fire or burning readily. Used especially to describe materials, fabrics, chemicals, or surfaces that do not ignite easily.
- Not flammable; incapable of catching fire or burning readily.
"The building is fitted with nonflammable insulation and safety equipment."
"The manufacturer specified nonflammable panels for the kitchen ceiling."
"Safety regulations require nonflammable storage containers for certain chemicals."
Adding non- to flammable changes the meaning completely: one catches fire, while the other is designed not to.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does nonflammable come from?
English nonflammable was formed by combining the prefix non-, meaning not, with flammable. Flammable derives from Latin flamma, meaning flame, through the related English verb flame. The related word inflammable also entered English with the prefix in-, but in modern usage it generally means flammable rather than nonflammable.
Related word forms
How nonflammable is actually used
Nonflammable is standard in technical, industrial, safety, and regulatory contexts. It is usually used before a noun, as in nonflammable material, and should not be confused with fire-resistant, which can indicate that a material withstands fire exposure for a limited time rather than that it cannot ignite.
Easily confused with nonflammable
Flammable means capable of catching fire or burning, whereas nonflammable means not flammable.
Inflammable normally means flammable, not the opposite, although it can cause confusion because its spelling resembles a word with the prefix in- meaning not.