Ottava rima is a rhyming stanza form of Italian origin. Originally used for long poems on heroic themes, it later came to be popular in the writing of mock-heroic works. Its earliest known use is in the writings of Giovanni Boccaccio.
The ottava rima stanza in English consists of eight iambic lines, usually iambic pentameters. Each stanza consists of three alternate rhymes and one double rhyme, following the ABABABCC rhyme scheme. The form is similar to the older Sicilian octave, but evolved separately and is unrelated. The Sicilian octave is derived from the medieval strambotto and was a crucial step in the development of the sonnet, whereas the ottava rima is related to the canzone, a stanza form.