1. Pen made from a bird's feather
   "The calligrapher dipped her quill pen in ink before writing";
   - quill pen
    
2. The hollow spine of a feather
   "The artist used a quill pen made from a large feather shaft";
   - calamus, shaft
    
3. Any of the larger wing or tail feathers of a bird
   "The eagle's quills were damaged, affecting its ability to fly";
   - flight feather, pinion, quill feather
    
4. A stiff hollow protective spine on a porcupine or hedgehog
   "The porcupine's quills rattled as it moved through the underbrush"

Derived forms: quills

Type of: pen, plume, rib, spine

Part of: Erinaceus europaeus, hedgehog, plume, porcupine, porky [N. Amer, informal], wing

Encyclopedia: Quill, John