iridium

noun
irid·​i·​um | \i-ˈri-dē-əm \

Definition of iridium 

: 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

Geologists soon found a similar iridium layer at the same geological strata in other parts of the world. Nina Burleigh, Newsweek, "We Can Save Ourselves From Earth-Killing Asteroids, But Someone Has to Pay," 11 June 2015 Iron meteorites: Typically consist of approximately 90 to 95% iron, with the remainder comprised of nickel and trace amounts of heavy metals, including iridium, gallium and sometimes gold. Perry A. Farrell, Detroit Free Press, "Which type of meteorite landed in Michigan? NASA 90% sure it knows," 17 Jan. 2018 In 2011, researchers led by Richard Masel, a chemist and CEO of Dioxide Materials in Boca Raton, Florida, tested a setup with silver and iridium oxide catalysts and a liquid electrolyte to promote the CO2 to CO reaction. Robert Service, Science | AAAS, "Two new ways to turn ‘garbage’ carbon dioxide into fuel," 1 Sep. 2017 When the Earth was forming, most iridium sank below the molten crust. Michael Ordoña, San Francisco Chronicle, "Nye documentary born in S.F.," 2 Nov. 2017 Project officials said once the iridium melts, the plutonium will be dispersed into the atmosphere. Washington Post, "NASA’s Saturn-orbiting Cassini spacecraft faces fiery finish," 12 Sep. 2017 Ni says the company is looking for cheaper options to replace iridium, a rare and expensive metal. Robert Service, Science | AAAS, "Two new ways to turn ‘garbage’ carbon dioxide into fuel," 1 Sep. 2017 There is reason to believe that some asteroids are rich in valuable metals, such as platinum and iridium. The Economist, "Space travelA new way of propelling spacecraft may open up the asteroid belt," 21 Sep. 2017 The most resilient bits will likely be the casings around its plutonium power source — the 72 marshmallow-sized pellets are encased in iridium and graphite containers designed to withstand re-entry into Earth's atmosphere or an explosion at launch. Author: Kenneth Chang, Alaska Dispatch News, "Cassini sends final images as it plunges toward Saturn," 15 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'iridium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of iridium

1804, in the meaning defined above

History and Etymology for iridium

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."

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Dictionary Entries near iridium

iridian

iridic

iridio-platinum

iridium

iridize

iridocyte

iridology

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Time Traveler for iridium

The first known use of iridium was in 1804

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More Definitions for iridium

iridium

noun
irid·​i·​um | \i-ˈri-dē-əm \

Kids Definition of iridium

: a hard brittle heavy metallic chemical element

iridium

noun
irid·​i·​um | \ir-ˈid-ē-əm \

Medical Definition of iridium 

: 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

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Rhyming Dictionary: Words that rhyme with iridium

Spanish Central: Translation of iridium

Nglish: Translation of iridium for Spanish Speakers

Britannica.com: Encyclopedia article about iridium

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