I. ˈən-dər-ˌwiŋ noun
Date: 1535
1. : one of the posterior wings of an insect
2. : any of various noctuid moths (especially genus Catocala ) that have the hind wings banded with contrasting colors (as red and black) — called also underwing moth
3. : the underside of a bird's wing
II. adjective
Date: 1896
: placed or growing underneath the wing
underwing rockets