underwing

 
Pronunciation: /ˈʌndəwɪŋ/

noun

  • 1the hindwing of an insect, especially when it is normally hidden by a forewing.
  • 2the underside of a bird’s wing.
  • 3 (also underwing moth) [usually with modifier] a moth with drab forewings and brightly coloured hindwings, typically yellow with a black terminal band.
    • Several genera in the family Noctuidae.