language evolution - When does a mistake become standard usage?

We all know that word meanings and usage change over time (though not all of us are happy about it). How long does a word have to be used in a particular way for that usage to be "okay"? At what point does it become "correct usage" and what determines that?

(It's hard to come up with an example that doesn't sound like peeving, so I'm making up a word.) If, for example, I started using the word "disregardless," most people would regard that as "wrong" or at least "not a real word." How many other people would have to use "disregardless" regularly for it to become an accepted word in the language? Does it matter if it's spoken or written? Does the "quality" of the speaker matter? (If the President uses the word, does that increase its "correctness" more than, say, when Bart Simpson uses it?) Is there a tipping point where a word goes from "made up" to "real" in the world at large, or is acceptance a gradual process throughout?

Answer

It depends on how useful a hole in the language the neologism is filling. If something becomes urgent as a topic of conversation and there was no word before, then it can quickly be accepted.

If a word is misspelled, people are more likely to resist the change, especially if the the old spelling is deeply entrenched, and it can take many years for the change to be accepted. It tends to go by critical mass; when enough 'respected' sources use a word - which used to mean broadsheet newspapers or literary magazines or novels or other books - then the lexicographers would pick it up and add it to the dictionaries, and the word would start to be accepted.

In the internet age, the process takes place much more rapidly. 'Weblog' gave way to 'blog' in almost no time at all.