willow borer
nounDefinition of willow borer
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: such 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 U.S.