Rondel

Webster's Dictionary of the English Language

·noun ·same·as Rondeau.

II. Rondel ·noun A small round tower erected at the foot of a bastion.

III. Rondel ·noun Specifically, a particular form of rondeau containing fourteen lines in two rhymes, the refrain being a repetition of the first and second lines as the seventh and eighth, and again as the thirteenth and fourteenth.