A lyric poem of fourteen lines. There are two common species of sonnet, distinguished by their rhyme scheme: the Italian and the Shakespearean.

The Italian (or Petrarchan) sonnet can be broken into two parts, the octave (eight lines) and the sestet (six lines). The octave typically rhymes abba abba; the sestet varies, sometimes cdecde, sometimes some variant of that.

The Shakespearean (or English) sonnet is instead three quatrains and a couplet: typically abab cdcd efef gg.

From the Guide to Literary Terms by Jack Lynch.
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Note: This guide is still in the early stages of development.
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