Source : Webster's Revised Unabridged Dictionary (1913)

Flower-de-luce \Flow"er-de-luce"\, n. [Corrupted fr.
   fleur-de-lis.] (Bot.)
   A genus of perennial herbs ({Iris}) with swordlike leaves and
   large three-petaled flowers often of very gay colors, but
   probably white in the plant first chosen for the royal French
   emblem.

   Note: There are nearly one hundred species, natives of the
         north temperate zone. Some of the best known are {Iris
         Germanica}, {I. Florentina}, {I. Persica}, {I.
         sambucina}, and the American {I. versicolor}, {I.
         prismatica}, etc.