[mass noun]the chemical element of atomic number 4, a hard grey metal(Symbol: Be) (化学元素)铍(符号: Be)
Beryllium is the lightest of the alkaline earth metals, and its chief source is the mineral beryl. It is used in the manufacture of light corrosion-resistant alloys and in windows in X-ray equipment
语源
mid 19th cent.: from beryl(from which it is derived) + -ium