Flammable and Inflammable Liquids

The vapours from flammable liquids burn. The vapours from inflammable liquids burn. So there is no difference worth mentioning apart from the spelling of the words.

Because of this confusion and the fact that both words mean the same thing, the word 'inflammable' should not be used now and 'flammable' is the preferred term.

hey tesser,

chutiye k patthe,saale angrej,bhosdi ke madar chod puri duniya ko english sikhate ho aur khud ko inflammable aur flammable mein difference nahi pata,that meant -

" u teach the whole world english and u dnt evn know the difference between inflammable and flammable,shame on ur english ass,mother fucker...."

The Difference Betweem Inflammable and Flammable Liquid:

Inflammable Liquid:A liquid substance which needs a physical igniting(ignited matchstick or any source of active or passive fire) agent is known as an inflammable liquid. Example: Petrol,Diesel etc

Flammable liquid:A liquid substance which may or may not need a physical igniting agent is known as a flammable liquid.Example:Nitro glycerine etc

That's not actually entirely true. Previous users were right, the terms flammable and inflammable have the SAME meaning. Infact the word "inflammable" pre-dates the term "flammable".

Inflammable -- To inflame, to excite, to arouse

This would be more properly used when talking about a person

Flammable --Easily ignited and capable of burning rapidly

This would be more proper for technical usage related to fire hazards.

However:
Usage Note: Historically, flammable and inflammable mean the same thing. However, the presence of the prefix in- has misled many people into assuming that inflammable means "not flammable" or "noncombustible." The prefix -in in inflammable is not, however, the Latin negative prefix -in, which is related to the English -un and appears in such words as indecent and inglorious. Rather, this -in is an intensive prefix derived from the Latin preposition in. This prefix also appears in the word enflame. But many people are not aware of this derivation, and for clarity's sake it is advisable to use only flammable to give warnings. (www.Dictionary.com)

You are correct on the usage of inflammable and flammable, although this clarification only applies to technical fields. You are incorrect on you examples however. Diesel will ignite under pressure without a spark. If you have a diesel car you will notice that there are no spark plugs.