Ever-alert reader Ken Buxton picks up my posting about dying expressions and points us all to this excellent site about Eggcorns, words and phrases whose use is mutating mainly but not only through ignorance:

In September 2003, Mark Liberman reported (Egg corns: folk etymology, malapropism, mondegreen, ???) an incorrect yet particularly suggestive creation: someone had written “egg corn” instead of “acorn”. It turned out that there was no established label for this type of non-standard reshaping.

Erroneous as it may be, the substitution involved more than just ignorance: an acorn is more or less shaped like an egg; and it is a seed, just like grains of corn. So if you don’t know how acorn is spelled, egg corn actually makes sense.

Here is a long list including strait/straight and ferment/foment and many other superb examples (a hare’s breath, peak one’s interest, right as reign, in lame man’s terms and so on)

Magnificent in itself and as an example of the Internet delivering collaborative networked insight at a high pace. Read on if you are interested in words.