名詞 cutworm:

1. North American moth whose larvae feed on young plant stems cutting them off at the ground

cut.worm

n.（名詞）
The larva of various moths of the family Noctuidae that feed on and destroy a wide variety of plants.
切根蟲：任一種夜蛾科的蛾子幼蟲，取食并破壞多種植物

來源：
[So called because many species eat through stems of plants]
[之所以如此稱呼是因為許多種類能咬穿植物的莖]