Pelargonium peltatum pe·lar·go·niumpeltatum uncommon noun 1. a commonly cultivated trailing South American plant with peltate leaves and rosy flowers Synonymsivy geraniumivy-leaved geraniumhanging geraniumPelargonium peltatum Related words Broader terms geranium Parts Pelargonium WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.