- any of several beetles, beetle larvae, or moth larvae that bore into the twigs of plants.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for twig borer
My trees are troubled with canker-worm, flathead borers, twig-borer, and leaf roller.
Am troubled some with canker-worm, twig-borer, and codling-moth.
My trees are troubled with roundhead borer, twig-borer, and grasshoppers.
My trees are troubled with flathead borer and twig-borer, and my apples with codling-moth.
My apple trees are troubled with canker-worm, twig-borer, and leaf-crumpler.