I suppose that a word is "real" as soon as someone, somewhere uses it and someone else understands what is meant. [I]f the word spreads and is understood by an increasing number of people and for an increasing length of time, then it is likely to reach the dictionary.

Well, that's a relief. So, irregardless is a word. I'd say this "rule" holds true for new meanings of old, real words, too. (Take that decimation, peevers!) Welcome to the "linguistics side", RC. "This time, I know, our side will win."

Ceci n'est pas un seing.