Triolet - Forme fixe

"A triolet is almost always a stanza poem of eight lines, though stanzas with as few as seven lines and as many as nine or more have appeared in its history. Its rhyme scheme is ABaAabAB and in 19th century English triolets often all lines are in iambic tetrameter, though in traditional French triolets from the 17th century on the second, sixth and eighth lines tend to be iambic trimeters followed by one amphibrachic foot each. In French terminology, a line ending in an iambic foot was denoted as masculine, while a line ending in an amphibrachic foot was called feminine. Depending on the language and era, other meters are seen, even in French. The first, fourth and seventh lines are identical, as are the second and final lines, thereby making the initial and final couplets identical as well. In a traditional French triolet, the second and third non-repeating lines rhyme with the repeating first, fourth, and seventh lines, while the non-repeating sixth line rhymes with the second and eighth repeating lines. However, especially in German triolets of the 18th and 19th centuries, one will see this pattern often violated. - Wikipedia"