The name dysprosium traces back to the Greek word dysprositos, meaning hard to get at or hard to obtain, a reference to the extraordinary difficulty chemists faced in separating it from the tangle of other rare earth elements surrounding it.

It was identified in 1886 by French chemist Paul-Émile Lecoq de Boisbaudran in Paris. Pure samples of the metal itself did not become available until around 1950, when Frank Spedding and his colleagues developed ion-exchange chromatography as a separation technique.

Dysprosium carries the chemical symbol Dy and atomic number 66. It belongs to the lanthanide series and is classified as a rare earth element. At room temperature it presents as a bright, silvery metallic solid. Its melting point is 1,412 degrees Celsius and its boiling point is 2,567 degrees Celsius.

The metal holds up reasonably well in air at room temperature but becomes reactive when heated, reacting with both water and air, and it dissolves in acids. Dysprosium has no known biological function and is considered to have low toxicity.

Its most commercially significant application is in neodymium-based permanent magnets. Incorporating dysprosium into these magnets dramatically improves their resistance to demagnetization at elevated temperatures, a property that is critical for the motors used in electric vehicles and for wind turbine generators.

Because dysprosium absorbs neutrons with considerable efficiency, it is also used in the control rods of nuclear reactors to help manage and regulate the fission reaction.

One unusual hazard: dysprosium powder can be ignited by a static electricity discharge, and burning dysprosium metal reacts with water to generate flammable hydrogen gas, meaning water actively worsens a dysprosium fire.