Hafnium (noun)

1. A metallic chemical element with the symbol Hf and atomic number 72.
2. A silvery-gray, lustrous, dense, and corrosion-resistant metal.
3. Used in aerospace, nuclear reactor and in tungsten alloys.

Origin:

From hafnia, the latin name for the city of copenhagen, where it was discovered.

Examples:

1. Hafnium is a chemical element with the symbol Hf and atomic number 72.
2. The hafnium isotopes are highly resistant to neutron bombardment, making them ideal for use in nuclear control rods.
3. Hafnium carbide is one of the most refractory compounds known, with a melting point of about 3900 °C.
4. Hafnium is used in aerospace, nuclear reactor and in tungsten alloys.
5. Hafnium is a chemical element with the atomic number 72 and is represented by the symbol Hf.