rondeau

noun pl. -·deaux-dōz

1. a short, lyrical poem of usually fifteen lines (three stanzas), with only two rhymes and with an unrhymed refrain at the end of the second and third stanzas
2. 1. rondo
   2. a medieval French monophonic or polyphonic song with many repetitions of two themes or phrases

Etymology: Fr, earlier rondel < rond, round