noun
1. also rose bug : a common No. American melolonthid beetle ( Macrodactylus subspinosus ) whose larva feeds on plant roots and the adults on leaves and flowers of various plants (as rosebushes, fruit trees, or grapevines)
2. : a common metallic green European scarabaeid beetle ( Cetonia aurata ) that feeds on plant roots as a larva and on leaves and flowers (as of roses) as an adult