lanthanum
/ˈlænθənəm/
noun
- A soft, silvery-white metallic chemical element (symbol La) that is used in making special types of glass, batteries, and camera lenses.
- The glass used in high-quality binoculars often contains a small amount of lanthanum.
- Lanthanum is added to some camera lenses to improve their ability to focus light.
- Scientists are studying lanthanum for use in new types of rechargeable batteries.