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any of several small trees of the genus Malus, in the rose family (Rosaceae), native to North America and Asia. Crabs are widely grown for their attractive growth habit, spring flower display, and decorative fruit. The fragrant five-petaled, white, pink, carmine, or purplish flowers appear early in showy masses. The fruits are much smaller and more tart than the common apple but are suitable for jellies, preserves, and cider. The tree itself is stiffer in form and more spiny than the common apple.