cuttlebone
/ˈkʌtəlˌboʊn/
noun
- The hard, brittle internal shell of a cuttlefish, often used as a calcium supplement for pet birds or as a polishing material.
- My parrot loves to sharpen its beak on a cuttlebone hanging in its cage.
- You can buy a cuttlebone at the pet store to give your bird extra calcium.
- Jewelers sometimes use powdered cuttlebone to polish delicate metal surfaces.