The short answer
Inflammable means capable of catching fire easily, and it means exactly the same thing as flammable, despite the confusing prefix. Inflammatory means likely to provoke anger, outrage, or conflict, usually describing words, speeches, or actions rather than physical materials. The two words are not related in meaning, even though they look similar on the page.
- Inflammable = flammable, catches fire easily
- Inflammatory = likely to provoke anger or conflict
Flammable vs. inflammable
Flammable and inflammable both describe materials that burn easily, which surprises many readers who expect the in- prefix to mean not. Here, in- comes from the Latin inflammare, meaning to set on fire, not from the negative prefix in- seen in words like inactive. Because the negative reading is such a common mistake, and because a mislabeled warning could be dangerous, most modern safety labels use flammable instead of inflammable to avoid any confusion at a glance.
What inflammatory means
Inflammatory describes language or behavior meant to stir up strong, usually angry, emotions. The politician's inflammatory remarks about his opponent drew immediate criticism online. A newspaper headline can be inflammatory if it exaggerates a conflict to provoke outrage rather than inform readers calmly. In medicine, inflammatory has yet another sense, describing conditions involving swelling or irritation in the body, such as an inflammatory response to an injury.
Correct examples in a sentence
Gasoline is highly inflammable and should be stored away from any open flame (not: gasoline is highly inflammatory). The coach's inflammatory comments after the game upset both teams' fans (not: the coach's inflammable comments after the game). Warehouse staff labeled the inflammable chemicals separately from the inflammatory posters someone had left on the wall.
Where each word shows up
Inflammable and flammable appear mainly on warning labels, safety data sheets, and instructions for handling materials like gasoline, paint thinner, or certain aerosols. Because a misread label could put someone in real danger, workplaces and shipping regulations increasingly favor flammable, along with the clearly worded non-flammable for materials that will not ignite, to remove any chance of a costly misunderstanding. Inflammatory, by contrast, turns up in news coverage, political commentary, and discussions of public speech, describing words chosen to provoke a reaction rather than materials that physically burn.
The two words can even appear in the same sentence without contradiction, since one describes a physical property and the other describes tone or intent. A safety inspector might note that inflammable chemicals were stored improperly, while a separate report criticizes a spokesperson's inflammatory response to the incident. Keeping the sentence's subject in mind, a material versus a statement, usually makes clear which word is needed.
Remember it
Think of a flame for both fire-related words: flammable and inflammable both contain something close to flame and both mean able to burn. For inflammatory, think of inflame emotions, since inflammatory words inflame anger the way fire inflames a room. Keeping the fire sense and the emotion sense in two separate mental boxes prevents the mix-up.
Frequently asked questions
Is inflammable the opposite of flammable?
No, they mean the same thing: both describe a material that catches fire easily. The word non-flammable is the true opposite.
What does inflammatory mean in a sentence?
It means likely to cause anger or conflict, usually describing remarks, speeches, or writing, as in his inflammatory comments sparked a public argument.
Why do safety labels say flammable instead of inflammable?
Because inflammable is often misread as meaning not flammable, manufacturers prefer flammable on warning labels to avoid dangerous confusion.
Try it with a real collection
Explore academic vocabulary or print a Frayer model to put these ideas into practice.