mi·cron | \ ˈmī-ˌkrän \

Definition of micron 

Examples of micron in a Sentence

Recent Examples on the Web

The main worry is with the tiniest motes — known as PM 2.5, particulate matter smaller than 2.5 microns across. Sara Morrison, USA TODAY, "In developing world, an expensive push to reduce cooking fire deaths falls short," 13 July 2018 For maximum effectiveness, the Ultra-Ever Dry must be applied in a tightly controlled, very thin, very even layer (a wet thickness of 76 to 127 microns for the bottom layer, according to the documentation). Lee Hutchinson, Ars Technica, "The Internet-demanded, partially scientific testing of Ultra-Ever Dry (in HD!)," 4 July 2018 These epidemiological studies exposed the health dangers of tiny particles of soot less than 2.5 microns in diameter. Margo Oge, Fortune, "Scott Pruitt Is Trying to Pull a Disappearing Act on Science. Here’s How It Would Impact Your Health," 25 June 2018 Lasers will etch miniaturized Wikipedia pages into square nickel sheets that are smaller than a postage stamp, each one measuring about half an inch (1.7 centimeter) wide and just 20 microns thick. Loren Grush, The Verge, "The Arch Foundation’s first step toward building a Lunar Library," 15 May 2018 Her winning image shows the 1 micron ridges connected by cross ribs on a butterfly wing which produce a brilliant iridescent color that never fades. Jason Daley, Smithsonian, "Breathtaking Bubbles, Butterfly Wings, and a Glowing Atom Take Top Prizes in Science Photo Contest," 14 Feb. 2018 But because the wavelength of near-infrared light is smaller than a micron, smaller than the smallest neuron, Jepsen believes the resolution of the technology is fine enough to make thoughts visible too. Jason Pontin, WIRED, "Thought-Reading Machines and the Death of Love," 16 Apr. 2018 The saga began in the early 1990s, when the EPA sought to regulate fine particulate matter known as PM2.5—dust and soot smaller than 2.5 microns in diameter. Steve Milloy, WSJ, "The EPA Cleans Up Its Science," 26 Mar. 2018 Because their diameter is so small (2.5 microns, or 1/120th the width of a strand of human hair), PM2.5 particles are known to make their way down into the farthest reaches of the lungs and even slip into the bloodstream. Zoë Schlanger, Newsweek, "Surprise! The Air Near Major Ports Is Bad for Kids," 17 May 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'micron.' 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 micron

1879, in the meaning defined above

History and Etymology for micron

New Latin, from Greek mikron, neuter of mikros small — more at micr-

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Statistics for micron

Last Updated

6 Aug 2018

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Time Traveler for micron

The first known use of micron was in 1879

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mi·cron | \ ˈmī-ˌkrän \

Medical Definition of micron 

: a unit of length equal to one millionth of a meter

called also micrometer, mu

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