Is 'Inflammable' the Opposite of 'Flammable'?

Well, you would really think that if something is flammable it could burn, and if something were inflammable that it couldn't burn, right? Because 'secure' and 'insecure', right?

WRONG. English is not particularly logical! Both 'flammable' and 'inflammable' indicate that something can burn. Of course, the adjective 'inflammable' is really based on the verb 'inflame', which means to set something alight, though now it is used as a figure of speech meaning saying or doing something provocative. But, it sure looks like the same 'in' as in 'insecure'!

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