rondel (n.)youdaoicibaDictYouDict[rondel 词源字典]
late 14c. as a type of verse, from Old French rondel "short poem," literally "small circle" (13c.), diminutive of roont (fem. roonde) "circular" (see round (adj.)). Metrical form of 14 lines with only two rhymes. So called because the initial couplet is repeated at the end.[rondel etymology, rondel origin, 英语词源]