Definition of cankerworm

• n. - The larva of two species of geometrid moths which are very injurious to fruit and shade trees by eating, and often entirely destroying, the foliage. Other similar larvae are also called cankerworms.
• n. - The larva of two species of geometrid moths which are very injurious to fruit and shade trees by eating, and often entirely destroying, the foliage. Other similar larvae are also called cankerworms.