A mind rhyme is a type of rhyme with a primary characteristic: that in this type of rhyme, an intended rhyming word remains unspoken, but only associated with the poem in the reader’s or listener’s mind. In other words, a poet or speaker will recite or write the rhyme in order to elicit a particular desired word without actually saying it. These kinds of rhyme are often popular as lowbrow communication intended to skirt prohibitions on obscenities, or to present a kind of risqué narrative implicitly.
In terms of their structure, mind rhymes can be either fixed verse or free verse. This kind of rhyming poem can be done in conventional poetic meters with fixed line lengths and rhymes, or in less regulated kinds of poetry. Many of these rhymes are done in popular traditional styles such as the five line limerick, which has a sort of tone and style that often complements the purposes of the mind rhyme.
Mostly, the rhymes themselves in mind rhymes are fairly concrete, though again, a primary characteristic of many of these types of rhymes is that the second rhyming word is not spoken, but substituted deliberately with another word that does not rhyme and which is not evidently relevant to the prior narrative. The final effect is that when the writer or speaker substitutes the word, he or she veers off into a subsequent narrative that contains its own structure.
In an abundance of instances of mind rhyme, the word that is left out of the rhyme is obscene or taboo in some way. That means that even the implicit connection of the rhyme may be uncomfortable to some listeners or readers. It’s important for a writer or speaker to know their audience in order to use good judgment about when to present this type of poem or rhyme.
The phenomenon of mind rhyme is in many ways like another somewhat unrelated use of rhyme that is often called rhyming slang. In rhyming slang, which is very common in the United Kingdom and some other language communities, a rhyming word is substituted for another rhyming word as a kind of informal code. The intent here is different from the intent of a mind rhyme; the general purpose of rhyming slang is simply to obscure the communication. Where some rhyming slang may start out as effective code, where only insiders understand what is being said, as a specific piece of rhyming slang catches on, the alternative meaning becomes evident to a wider audience.