Source : Webster's Revised Unabridged Dictionary (1913)

Peony \Pe"o*ny\, n.; pl. {Peonies}. [OE. pione, pioine, pioni,
   OF. pione, F. pivoine, L. paeonia, Gr. ?, fr. ?, ?, the god
   of healing. Cf. {P[ae]an}.] (Bot.)
   A plant, and its flower, of the ranunculaceous genus
   {P[ae]onia}. Of the four or five species, one is a shrub; the
   rest are perennial herbs with showy flowers, often double in
   cultivation. [Written also {p[ae]ony}, and {piony}.]

Source : WordNet®

peony
     n : any of numerous plants widely cultivated for their showy
         single or double red or pink or white flowers [syn: {paeony}]