Eggcorn

From Wikipedia:

An eggcorn is the alteration of a phrase through the mishearing or reinterpretation of one or more of its elements, creating a new phrase having a different meaning from the original but which still makes sense and is plausible when used in the same context. The word “eggcorn” is itself an eggcorn, derived from acorn. Eggcorns often arise as people attempt to make sense of a stock phrase that uses a term unfamiliar to them, as for example replacing “Alzheimer’s disease” with “old-timers’ disease”, or 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. 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” being replaced with the more common word “foul” in order to convey the cruel/underhand meaning of the phrase as the speaker understands it.

Eggcorns are of interest to linguists as they not only show language changing in real time, but can also shed light on how and why the change occurs.

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Examples

• “baited breath” for “bated breath”
• “beckon call” for “beck and call”
• “damp squid” for “damp squib”
• “ex-patriot” for “expatriate”
• “the feeble position” for “the fetal position”
• “for all intensive purposes” for “for all intents and purposes”
• “free reign” for “free rein”

Link to the rest at Wikipedia