Source : Webster's Revised Unabridged Dictionary (1913)

Gardenia \Garde"ni*a\, n. [NL.] (Bot.)
   A genus of plants, some species of which produce beautiful
   and fragrant flowers; Cape jasmine; -- so called in honor of
   Dr. Alexander Garden.

Source : WordNet®

gardenia
     n : any of various shrubs and small trees of the genus Gardenia
         having large fragrant white or yellow flowers