One of my all-time favorite Simpsons moments is when the quack doctor, Dr. Nick Rivera, insists when a flaming ring lands on a tank of laughing gas (I think it is...), "Don't worry. It's inflammable." and is promptly exploded. To which he replies, "Inflammable means flammable? What a country."
I tend to agree. ;-) This is one of those weirdo things that I know but never really got. (And anyone who read last week's post on 'reckless' knew I was going to do this one this week, didn't you? LOL.) What gets me is that both are perfectly cromulent (to steal another Simpsonsism...)--a.k.a valid for those of you who have never watched the show. ;-) Either is acceptable. Both have entries in the dictionary.
Inflammable is definitely the earlier of the two words, from the Latin inflammare, which means "to set on fire" but often in a figurative sense--to inflame one's passion, to inflame a crowd with anger. But it's been around in English since the 15the century, in both that sense, in the sense of a medical inflammation, and taking on the literal sense on fire around 1600.
Flammable is said to be taken directly from the Latin flammare, which is ONLY the literal "set on fire." Literally flame + able. And some experts think it has come into use solely to eliminate confusion in commercial situations that involve things that go boom. ;-)
So in this day and age, if you see a container marked with that oh-so-lovely image, it's more likely to have "flammable" written on it than "inflammable." (Just for you, Dr. Nick!) But when it comes to igniting the inflammable emotions of a mob, that 'in' is always going to be there. ;-)
Hope everybody has a great week!