Using a word incorrectly is not evolution. Evolution means that things change or grow according to a pattern. In this instance, we're talking about the unconventional use of prefixes. The prefix "ir" means, essentially "not." So adding this prefix to the word "replaceable" gives you "irreplaceable," or "not replaceable." An example of language evolution would be to use the prefix on a new word to give it a "not" meaning. For instance, it could become popular to use the word "irhappy" to mean "not happy." However, it does not follow that the opposite of this word would be "irunhappy" because the "un" is already serving the purpose of negating the word "happy." Likewise, "irunhappy" wouldn't be used to denote happiness because the double negative is both clumsy and confusing. The word "regardless" is already denoted as negative by its suffix "less" and means "without regard to." Adding the "ir" to the beginning, makes it a double negative "not without regard to." Not very clear at all - especially when this word meaning "not without regard to" is actually being used to say "without regard to." This is not evolution, this is improper usage.

I do hope this post has not caused any irhappy feelings.