noun (n)

• English form of rondeau having three triplets with a refrain after the first and third(noun.communication)

  source: wordnet30
• round piece of armor plate that protects the armpit(noun.artifact)

  source: wordnet30
• (heraldry) a charge in the shape of a circle(noun.artifact)

  Example:
  A hollow roundel.
  

  Synonym:
  annulet
  

  source: wordnet30
• A rondelay.(noun)

  source: webster1913