The misuse of a word that has a similar sound to the correct one is officially called a "malapropism." It's surprisingly common, particularly within the extensive English vocabulary, and, as we can see, often occur in everyday speech. But authors will sometimes use a malapropism because of its humorous effect as a literary device.
The term comes from Richard Brinsley Sheridan's 1775 play The Rivals. In it, the character Mrs. Malaprop does exactly that—replaces words with humorous alternatives to produce a laugh. Mrs. Malaprop was likely named after the French phrase "mal à propos," which translates to "incorrectly or poorly placed." In English, the borrowed word is written as "malapropos," meaning "inappropriate or inappropriately."
One synonym for "malapropism" is "dogberry," which also comes from literature, in this case, William Shakespeare. In Much Ado About Nothing, the character Dogberry also frequently utters malapropisms for humor.
A more recent popular example comes from the late 1970s, when English comedian Les Dawson took advantage of the popularity of Polaroid's instant cameras which were all the rage at the time.
Dawson had created an alter ego called Cissie who was prone to making silly comments. In a much-loved episode of his show, Cissie refers to "one of those paranoid cameras."
This hilarious bit may well have been inspired by Dawson’s signature comedic device – his piano playing. He was an accomplished musician but would deliberately play the wrong notes in his performances.
Sometimes these slips of the tongue have unfortunate effects. A stream of broadcasters have slipped up on national TV and radio over the name of British politician Jeremy Hunt and have replaced his surname with a similar sounding, impolite word.
Linguist Patrycja Strycharczuk explained that this phenomenon may occur as the person is anticipating an upcoming word starting with a similar sound (such as “Conservative Party” or “Culture Secretary”). There is also the fact that a rude word is memorable and may accidentally pop in.
As University of Essex linguists Amanda Cole, Connor Youngberg, and Faith Chiu pointed out, what is often referred to as "mispronunciations" or "slips of the tongue" are not just embarrassing mistakes, they can also be language changes in action. In fact, sometimes mispronunciations become so common that they become our normal way of speaking. (In parts of the US, people may be heard to regularly say "perty" as opposed to "pretty".)
A historical example is the word "apron" which actually comes from the Middle English "napron." It derived from the French naperon (small table cloth), but over time, people turned "a napron" into "an apron," resulting in the word we know today.
"Speech 'errors' are a great resource for linguists," Cole, Youngberg, and Chiu wrote. "They tell us about how people use and process language. They can also sometimes tell us about how language might change. This poses the question: how many people have to regularly 'mispronounce' a word until we begin to consider that the new pronunciation is just the regular, normal way of saying it?" So maybe 'Bone Apple Tea' is actually a glimpse into our phonetic future!
