Noun | 1. | Cestrum - genus of fragrant tropical American shrubs asterid dicot genus - genus of more or less advanced dicotyledonous herbs and some trees and shrubs family Solanaceae, potato family, Solanaceae - large and economically important family of herbs or shrubs or trees often strongly scented and sometimes narcotic or poisonous; includes the genera Solanum, Atropa, Brugmansia, Capsicum, Datura, Hyoscyamus, Lycopersicon, Nicotiana, Petunia, Physalis, and Solandra Cestrum diurnum, day jessamine - West Indian evergreen shrub having clusters of funnel-shaped white flowers that are fragrant by day Cestrum nocturnum, night jasmine, night jessamine - West Indian evergreen shrub having clusters of funnel-shaped yellow-white flowers that are fragrant by night |