noun
: any of several moths whose larvae eat the foliage of the walnut: as
a. : regal moth
b. : imperial moth
c. : luna moth
d. : any of several red underwings of the genus Catocala
e. : a dagger moth ( Acronicta americana ) found also on the maple
f. : any of three arctiid moths of the genus Halisidota (H. caryae, H. tesselaris, H. maculata)
g. : a moth ( Datana integerrima ) whose larva feeds on and often defoliates walnut, hickory, birch, oak, chestnut, linden, and apple