flammable
flame + -able
https://gyazo.com/4cc9a99ac1d22f4c8ae730a8917bf66e
source: By Government of the United States - "Emergency Response Guidebook." U.S. Department of Transportation, 2004, pages 16-17., Public Domain
adjective
easily set on fire:
〈材質･物質が〉可燃性の, 引火性の, 火のつきやすい (!flammableと同義語であり, 反対語ではないので注意; ↔ nonflammable)
e.g. the use of highly flammable materials.
DERIVATIVES
flammability |ˌflaməˈbilədē| noun
ORIGIN
early 19th century: from Latin flammare, from flamma ‘a flame’.
USAGE
The words flammable and inflammable mean the same thing, but flammable is preferred to avoid confusion: see usage at inflammable.
The words inflammable and flammable both have the same meaning, ‘easily set on fire.’ This might seem surprising, given that the prefix in- normally has a negative meaning (as in indirect and insufficient), and so it might be expected that inflammable would mean the opposite of flammable, i.e., ‘not easily set on fire.’ In fact, inflammable is formed using a different Latin prefix in-, which has the meaning ‘into’ and here has the effect of intensifying the meaning of the word in English. Flammable is a far commoner word than inflammable and carries less risk of confusion.