The placement of an intensifier put between the syllables of a three- or more syllable word for emphasis

Question

Playing an online lexicogrammar game, I met the word "unbelievable" written with a swear word "f_cking" inserted between the first and second syllables: "un-f_cking-believable".

I understand that it is done for emphasis, but I don't understand the placement of the intensifier f_cking:

Why wasn't it inserted before the stressed syllable as goes the explanation of the mistake I made? Are there any exceptions to the rule? Has it anything to do with the negative prefix un-? If yes, is there's more to it than that that I should bear in mind using an intensifier between syllables?

Answer 1

This is an example of tmesis, and it is widely used in English.

Example:

That play last night was un-freakin'-believable.

Note that this is often a colloquial usage, but even the best writers have used it from time to time and it doesn't have to be vulgar.

Example from Shakespeare, Romeo and Juliet:

“This is not Romeo, he's some other where.”

An English professor I had as an undergraduage said he liked to think of tmesis placement as in a tent where the fabric of the tent is best supported, the stressed syllables being the poles of said tent. Syllables before and after the tmesis can be unstressed as long as they are preceded or followed by stressed syllables.

We see that the placement is not always before a stressed syllable (as in "abso-freakin'-lutely"). For example, in unbelievable it usually comes before an unstressed syllable, but in fact it would not be surprising to hear it as "unbe-freakin'-lievable" as well. In fantastic it would come between two stressed syllables ("fan-freaking-tastic") and so on. It never comes before an unstressed syllable or series of syllables at the end of a word ("unbeliev-freakin'-able"?), however.