Its origins are possibly related to the Old English maða meaning 'maggot' or from the root of midge which until the 16th century was used mostly to indicate the larva, usually in reference to devouring clothes.

[7] The caterpillar of the spongy moth (Lymantria dispar) causes severe damage to forests in the northeastern United States, where it is an invasive species.

In tropical and subtropical climates, the diamondback moth (Plutella xylostella) is perhaps the most serious pest of brassicaceous crops.

[8] Several moths in the family Tineidae are commonly regarded as pests because their larvae eat fabric such as clothes and blankets made from natural proteinaceous fibers such as wool or silk.

There are some reports that they may be repelled by the scent of wood from juniper and cedar, by lavender, or by other natural oils; however, many consider this unlikely to prevent infestation.

Some, like the Luna, Polyphemus, Atlas, Promethea, cecropia, and other large moths do not have mouth parts.

[9] Items of fabric infested by clothes moth larvae may be treated by freezing them for several days at a temperature below −8 °C (18 °F).

The mopane worm, the caterpillar of Gonimbrasia belina, from the family Saturniidae, is a significant food resource in southern Africa.

Baculoviruses are parasite double-stranded DNA insect viruses that are used mostly as biological control agents.

There is evidence that ultrasound in the range emitted by bats causes flying moths to make evasive maneuvers.

[22] Some studies indicate that certain species of moths, such as those belonging to the families Erebidae and Sphingidae, may be the key pollinators for some flowering plants in the Himalayan ecosystem.

By maintaining a constant angular relationship to a bright celestial light, such as the moon, they can fly in a straight line.

Celestial objects are so far away that, even after travelling great distances, the change in angle between the moth and the light source is negligible; further, the moon will always be in the upper part of the visual field, or on the horizon.

When a moth encounters a much closer artificial light and uses it for navigation, the angle changes noticeably after only a short distance, in addition to being often below the horizon.