Sicilian octave
The Sicilian octave (Italian: ottava siciliana or ottava napoletana, lit. "Neapolitan octave") is a verse form consisting of eight lines of eleven syllables each, called a hendecasyllable. The form is common in late medieval Italian poetry. In English poetry, iambic pentameter is often used instead of syllabics. The form has a prescribed rhyme scheme (A-B-A-B-A-B-A-B). Although only the final two rhymes are different from the much more common ottava rima, the two eight-line forms evolved completely separately. According to the Princeton Encyclopedia of Poetry and Poetics, scholars disagree on the origin of the Sicilian octave, but all agree that it is related to the development of the first eight lines of the sonnet (called the octave). It is not clear whether the octave emerged first and influenced the sonnet or vice versa.