A rhyme is a repetition of identical or similar sounds in two or more different words and is most often used in Poetry. The word "rhyme" may also refer to a complete rhyming Couplet or short poem that uses verses (see Nursery rhyme).
The spelling "rime" survives in English however, as a rare alternative spelling. A distinction between the spellings is also sometimes made in the study of Linguistics and Phonology, where "rime/rhyme" is used to refer to the nucleus and coda of a Syllable. In this context, some prefer to spell this "rime" to separate it from the poetic rhyme covered by this article (see Syllable rime).
When words within a single line are rhymed, it is called an Internal rhyme.
Categories of rhyme include:
A Rhyme scheme is the pattern of rhyming lines in a poem.
Old English poetry is mostly Alliterative verse. One of the earliest rhyming poems in English is The Rhyming Poem.
Some words in English, such as orange, are commonly regarded as having no rhyme. Although a clever poet can get around this (for example, by rhyming "orange" with "door hinge"), it is generally easier to move the word out of rhyming position or replace it with a Synonym ("orange" could become "amber").
The rime riche ("rich rhyme") of three phonemes is classically more admired. To an Anglophone ear, by contrast, this often sounds like a very weak rhyme. For example, an English perfect or identity rhyme, such as homophones flour and flower, would seem weak, whereas a French rhyme of homophones doigt and doit qualifies as rime riche. Rime richissime ("very rich rhyme") is a rhyme of more than three phonemes.
Here is a Holorime (an extreme example of rime richissime spanning an entire verse):
Alphonse Allais was a notable exponent of holorime.
Classical French poetry also used to have a complex set of rules for rhymes that goes beyond how words merely sound. It include whether the unsounded letter s, x, z and e are present at the end of each line and are often considered part of the meter of the poem.
For example the singular feminine "une souris", which means "a mouse", would be a masculine plural rhyme.
A set of rhymes is only valid if the sound, number and gender all match. In the 19th century, Baudelaire made some poems that dropped the sound requirement. In those poems, words that ended in the same spelling were considered as valid rhymes even if they sounded different. He called those "rhymes for the eye", "rimes pour l'œil."
A feminine rhyme cannot follow a different feminine rhyme and a masculine rhyme cannot follow a different masculine rhyme. Masculine and feminine rhymes must alternate.
If these rules were to be applied to English "there" and "fair" would not rhyme; and "lean" and "cuisine" would not rhyme either. Furthermore, a couplet rhyming in "-er", like "better" and "after", could not be followed by a couplet rhyming in "-ight", like "right" and "fight". These would be two different masculine rhymes "touching" each other. There must be a feminine rhyme in between.
That is why, in French sonnets, the first four lines (1 to 4) and the second four lines (5 to 8) often have the exact same rhymes, with the structure abba abba: it allows for a mirror gender structure. The edge lines of both quatrains (lines 1, 4, 5 and 8) can be of one gender and the middle lines (lines 2, 3, 6 and 7) can be of the other. The trick is that the fourth and fifth lines of the sonnet must be the same, or else the fourth and fifth lines would have to alternate gender. Of course, a structure like abba acca would technically follow the rules, but it would be very ugly.
All this comes from the fact that the marks for the plural and the gender of words that are now silent used to be sounded, but they did not count as being part of the meter. These rhyming rules are almost never taken into account from the 20th century on. Still, they are in almost all of the pre-20th century French verse texts. For example all of the French plays in verse of 17th century alternate masculine and feminine Alexandrine couplets.
Medieval poetry may mix Latin and Vernacular languages. Mixing languages in verse or rhyming words in different languages is termed Macaronic.