astatine
noun [ U ] uk/ˈæs.tə.tiːn/ us/ˈæs.tə.tiːn/
(symbol At)砹（地球表面最为稀少的一种放射性化学元素）
a chemical element that is radioactive and is the rarest natural element on the Earth's surface
The properties of astatine remain a mystery. 砹的属性仍然不为人知。
- More examples
- The lowest element in this group is also a highly radioactive and rare element, astatine.
- Fluorine and astatine are halogens.
- What is the physical state of astatine at room temperature?