'armyworm' definitions:

Noctuid moth larvae that travel in multitudes destroying especially grass and grain [syn: armyworm, army worm, Pseudaletia unipuncta]

Moth whose destructive larvae travel in multitudes [syn: armyworm, Pseudaletia unipuncta]

Larva of fungus gnat that feed on cereals and other grains; they march in large companies in regular order when the food is exhausted