Eggcorn

Eggcorns often arise as people attempt to make sense of a stock phrase that uses a term unfamiliar to them,[3] as for example replacing "Alzheimer's disease" with "old-timers' disease",[2] or William Shakespeare's "to the manner born" with "to the manor born".

Eggcorns arise when people attempt to use analogy and logic to make sense of an expression – often a stock one – that includes a term which is not meaningful to them.

[3] For example, the stock expression "in one fell swoop" might be replaced by "in one foul swoop", the infrequently used adjective "fell" (for "fierce", "cruel", or "terrible"[4]) being replaced with the more common word "foul" in order to convey the cruel/underhand meaning of the phrase as the speaker understands it.

[3] The term egg corn (later contracted into one word, eggcorn) was coined by professor of linguistics Geoffrey Pullum in September 2003 in response to an article by Mark Liberman on the website Language Log, a group blog for linguists.

[5] In his article, Liberman discussed the case of a woman who had used the phrase egg corn for acorn, and he noted that this specific type of substitution lacked a name.