A plum is a flowering fruit tree, and it's also the name of the fruit that grows on it. Plums are small, dark reddish purple, and sweet. Plums have an edible, smooth skin, juicy flesh, and a hard pit in the middle. When plums are dried, they're called prunes.

plum, any of various trees or shrubs in the genus Prunus (family Rosaceae) and their edible fruits. Plums are closely related to peaches and cherries and are widely eaten fresh as a dessert fruit, cooked as compote or jam, or baked in a variety of pastries. The European plum (P. domestica) and the Japanese plum (P. salicina) are grown commercially for their fruits, and a number of species, including the purple-leaf plum (P. cerasifera), are used as ornamental plants for their attractive flowers and leaves.