Source : Webster's Revised Unabridged Dictionary (1913)

Ricinus \Ric"i*nus\, n. [L., the castor-oil plant.] (Bot.)
   A genus of plants of the Spurge family, containing but one
   species ({R. communis}), the castor-oil plant. The fruit is
   three-celled, and contains three large seeds from which
   castor oil iss expressed. See {Palma Christi}.

Source : WordNet®

Ricinus
     n : a genus of herb having only one known species: castor-oil
         plant [syn: {genus Ricinus}]