From The Princeton Encyclopedia of Poetry and Poetics
(from It. villanella, a rustic song, villano, a peasant). As known today, a 19-line poem with two rhymes and two refrain lines, in the form AJoA 2abAj abA2 abA¡ abA2 abA¡ A2, where capital letters indicate refrains. Fr. poet Théodore de Banville compared the interweaving a, b, and refrain lines to "a braid of silver and gold threads, crossed with a third thread the color of a rose."