iridium

noun

irid·​i·​um i-ˈri-dē-əm 

: a rare silver-white hard brittle very heavy metallic element see Chemical Elements Table

Examples of iridium in a Sentence

Recent Examples on the Web

But recent theoretical work suggests the iridium in another compound, IrO3, is more reactive, potentially allowing chemists to use smaller quantities. —science.org, 23 Jan. 2025

Electrolyzers that can operate flexibly, to utilize intermittent renewables like wind and solar, often rely on precious metals like iridium, which are not only expensive but also are produced in small amounts currently. —IEEE Spectrum, 29 Jan. 2025

The mainstay electrodes used for brain mapping are disks of platinum iridium set in silicon. —Emily Mullin, WIRED, 26 Sep. 2024

The researchers also report the discovery of iridium layers in the sediments surrounding MAPCIS. —David Bressan, Forbes, 26 Sep. 2024

Word History

Etymology

Greek īrid-, îris "rainbow, iridescent halo around the moon, a flame, etc., iris entry 1" + New Latin -ium -ium; from the colors produced by dissolving it in hydrochloric acid

Note: The word iridium was introduced by the English chemist Smithson Tennant (1761-1815) in Philosophical Transactions of the Royal Society, 1804, Part II, p. 414: "As it is necessary to give some name to bodies which have not been known before, and most convenient to indicate by it some characteristic property, I should incline to call this metal Iridium, from the striking variety of colours which it gives, while dissolving in marine acid." See also osmium.

First Known Use

1804, in the meaning defined above

Rhymes for iridium

• clostridium
• cranidium
• cymbidium
• peridium
• presidium
• pygidium
• rubidium
• cryptosporidium
• idiom

Kids Definition

iridium

noun

irid·​i·​um ir-ˈid-ē-əm 

: a rare silver-white hard brittle very heavy metallic element see element

Medical Definition

iridium

noun

irid·​i·​um ir-ˈid-ē-əm 

: a silver-white hard brittle very heavy metallic element of the platinum group used especially in hardening platinum for alloys (as for surgical instruments)

—symbol Ir see Chemical Elements Table