rondel

noun5

1. •
   A metric form of verse using two rhymes, usually fourteen 8- to 10-syllable lines in three stanzas, with the first lines of the first stanza returning as refrain of the next two.
2. •
   The verse form rondeau.
3. •
   (historical) A long thin medieval dagger with a circular guard and a circular pommel (hence the name).
4. •
   A rondelle, (small) circular object.
5. •
   (historical) A small round tower erected at the foot of a bastion.