1. Tuft of small stiff feathers on the first digit of a bird's wing
   "The alula helps stabilize the bird during flight";
   - bastard wing, spurious wing
    
2. Scalelike structure between the base of the wing and the halter of a two-winged fly
   "The alula helps stabilize the fly during flight";
   - calypter

Derived forms: alulae

Type of: plume, squama

Part of: fly, wing

Encyclopedia: Alula, Somalia