underwings Definition

one of the posterior wings of an insect

any of various noctuid moths (especially genus Catocala) that have the hind wings banded with contrasting colors (such as red and black) —called also underwing moth

the underside of a bird's wing

one of the movable feathered or membranous paired appendages by means of which a bird, bat, or insect is able to fly; also : such an appendage even though rudimentary if possessed by an animal belonging to a group characterized by the power of flight

any of various anatomical structures (as of a flying fish or flying lemur) providing means of limited flight

an appendage or part resembling a wing in appearance, position, or function: such as