WordNet (r) 3.0 (2006):

castor bean plant
    n 1: large shrub of tropical Africa and Asia having large
         palmate leaves and spiny capsules containing seeds that are
         the source of castor oil and ricin; widely naturalized
         throughout the tropics [syn: castor-oil plant, castor
         bean plant, palma christi, palma christ, Ricinus
         communis]