Tmesis is an interesting word that is seldom used, though most of us have used a tmesis, or at least heard someone else use a tmesis. It is considered a literary device, which is a tool used by speakers and writers in order to produce a certain effect. We will examine the definition of tmesis, where the word came from and some examples of its use in sentences.
A tmesis is a word that includes another word inside it. When constructing a tmesis, the speaker splits a word in order to insert another word inside it, usually in order to be humorous or to emphasize something. Some examples of a tmesis are fan-frickin’-tastic, some-other-where, zero-dark-thirty. Some definitions of the term tmesis state that the word being split must be a compound word, though other definitions state that any word may be split in order to become a tmesis. The word tmesis has been in use since the 1500s and is derived from the Greek word tmesis which means a cutting. The plural form of tmesis is tmeses. While tmeses are often used in conversation, they are rarely seen in print as this manner of speaking is informal.
There’s another term, tmesis, which could maybe work, but linguists disagree on the definition of tmesis, and many people aren’t sure how to pronounce it. (The Week)
As Guy Davenport pointed out in the 1980s in an essay terribly entitled ‘Transcendental Satyr’, Cummings’s ‘eccentric margins, capricious word divisions, vagrant punctuation, tmeses and promiscuously embracing parentheses’ resemble the texts he read as a Greek major at Harvard. (The London Review of Books)