batwing

noun7

1. •
   The wing of a bat, or its shape.

   • The junk was nearer, beating in toward the island, her brown batwing sail suddenly tall and terribly conspicuous against the sky. — 1977
2. •
   A long sleeve with a deep armhole, tapering toward the wrist.
3. •
   One of a pair of swinging doors which typically do not lock nor cover the full vertical range of the doorway (leaving a large gap at the top and bottom), common especially in saloons.

   • A tall figure stepped up to the batwing doors of the saloon as Tommy and Matt passed. — 2012
4. •
   (slang) An area of flabby fat under a person's arms.
5. •
   A heart-shaped rollercoaster feature with two inversions.
6. •
   Several South or Southeast Asian species of tailless dark swallowtail butterflies in the genus Atrophaneura.
7. •
   [before a noun] An exercise or posture on the stomach wherein a dumbbell row or lateral raise is performed.