The term 'platinum-group element' refers to a group of six elements found in the periodic table: platinum, palladium, rhodium, ruthenium, osmium, and iridium. Iridium is one of these elements, and it is represented by the seven-letter word 'iridium'. Iridium is a silvery-white metal that is highly resistant to corrosion and oxidation. It is used in a variety of applications, including electrical contacts, spark plugs, and medical implants.