The Collaborative International Dictionary of English v.0.48:

Fleuron \Fleu`ron"\, n. [F., fr. OF. floron. Cf. Floroon.]
   A flower-shaped ornament, esp. one terminating an object or
   forming one of a series, as a knob of a cover to a dish, or a
   flower-shaped part in a necklace.
   [Webster 1913 Suppl.]