Adj. It can easily burn ( and cause an explosion violent ). It comes from the Latin noun "flamma": calls, and the ending 'able': capable of. Synonym: flammable. May seem contradictory, flammable and flammable are equivalent, because in this case the preposition 'in' is not negative. Inside, means that there is a principle - property possibility to generate flames inside. Pure Spanish is flammable. The use of flammable is under the influence of English, notwithstanding that in this language there is also the 'inflammable' diction, but - by custodial misinterpretation of 'in'-, preferably 'flammable' has been used.