Definitions

1. noun

A rare and highly corrosion-resistant heavy metal, a chemical element with the symbol Ir and atomic number 77, used in alloys and as a catalyst.

“The scientist studied the properties of iridium in the Earth’s core.”

2. noun

A unit of time, equal to one billionth of a second, used in physics and astronomy.

“The physicist measured the duration of the event in iridium units.”