Flammable or inflammable?
flammable is an adjective meaning “Capable of burning”; inflammable is an adjective meaning “Capable of burning”. In written English (wordfreq, 2021 data) flammable is about 11 times as common as inflammable.
What is the difference between flammable and inflammable?
| flammable | inflammable | |
|---|---|---|
| Part of speech | adjective, noun | adjective, noun |
| Meaning | Capable of burning Easily set on fire Any flammable substance | Capable of burning Easily set on fire Any inflammable substance |
| Example | Near-synonym: ignitable | none recorded |
| Pronunciation | /ˈflæməbl̩/ | /ɪnˈflæməbəl/ [ɪnˈflæməbl̩] ~ [ɪɱˈflæməbl̩] [ɪnˈfleə̯məbəl] |
| In writing | 1.5 times per million words | about once in every 7 million words |
Sources: flammable and inflammable in the English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0); written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
Every current meaning of flammable and inflammable
flammable
- 1
Capable of burning
Near-synonym: ignitable
- 2
Any flammable substance
- 3
Easily set on fire
Near-synonym: ignitable
- 4
Subject to easy ignition and rapid flaming combustion
- 5
Very likely to cause fighting or controversy; extremely contentious
inflammable
- 1
Capable of burning
- 2
Any inflammable substance
- 3
Easily set on fire
- 4
Easily excited; set off by the slightest excuse; easily enraged or inflamed
Source: the English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0); obsolete, archaic, dialect and rare senses left out.
Which is more common, flammable or inflammable?
flammable appears 1.5 times per million words; inflammable about once in every 7 million words.
flammable 1.5 times per million wordsinflammable about once in every 7 million words
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How many people search flammable vs inflammable?
“flammable vs inflammable” is searched about 5,400 times a month on Google and 100 on Bing in the United States. Google counts close variants of a query together (“inflammable vs flammable”, “flammable or inflammable”).
Sources: Google Ads keyword data through DataForSEO and Microsoft Advertising keyword data through DataForSEO, the average month from September 2025 to August 2026.