Source : Webster's Revised Unabridged Dictionary (1913)

Chrysanthemum \Chrys*an"the*mum\, n. [L., fr. Gr. ?; chryso`s
   gold + ? flower.] (Bot.)
   A genus of composite plants, mostly perennial, and of many
   species including the many varieties of garden chrysanthemums
   (annual and perennial), and also the feverfew and the oxeye
   daisy.

Source : WordNet®

chrysanthemum
     n 1: the flower of a chrysanthemum plant
     2: any of numerous perennial Old World herbs having showy
        brightly colored flower heads of the genera Chrysanthemum;
        Argyranthemum; Dendranthema; Tanacetum; widely cultivated