noun
1. : any of several small bronzy longicorn beetles of the genus Agrilus that bore in the sapwood of the willow tree and often kill it: as
a. : a beetle ( A. politus )
b. : a beetle ( A. anxius ) that infests also poplars and birches
2. : poplar borer
3. : a European weevil ( Cryptorhynchus lapathi ) introduced and destructive to willows in the eastern United States