iridium
n. uncountablen. a very hard and heavy metal that is almost impossible to melt. It is one of the rarest elements on Earth and is often used in special tools and jewelry.
n. a hard, silvery-white, corrosion-resistant transition metal of the platinum group. It is the most corrosion-resistant and the second-densest element in the periodic table.
The scientist used a tiny amount of iridium to make the pen tip.
Because of its extreme durability, iridium is often alloyed with platinum to create spark plugs for high-performance engines.
The geological layer rich in iridium found at the Cretaceous-Paleogene boundary provides strong evidence for the impact hypothesis regarding the extinction of the dinosaurs.
From international scientific vocabulary, from the New Latin.