mi·​cron | \ ˈmī-ˌkrän How to pronounce micron (audio) \

Definition of micron

Examples of micron in a Sentence

Recent Examples on the Web

Lewis said smoke is made of small particles, some smaller than 2.5 microns in diameter. oregonlive.com, "What are the long-term health effects from wildfire smoke? Oregon doctors say it’s something they’re still learning about.," 22 July 2019 The Mylar material composing the sail is just 4.5 microns thick, or about one-tenth as thick as a human hair. Eric Berger, Ars Technica, "One legacy of Carl Sagan may take flight next week—a working solar sail," 20 June 2019 More insidiously, people are also inhaling noxious fine particles measuring less than 2.5 microns, or a fifth the size of a particle of dust or pollen. Daniel Oberhaus, WIRED, "The Health Effects of Wildfire Smoke May Last a Lifetime," 27 June 2019 The smallest particle a human eye can see is about 40 microns. Stephen Leahy, National Geographic, "Microplastics are raining down from the sky," 15 Apr. 2019 Imagine that the laws of physics prevent you from measuring anything smaller than 0.001 micron. Quanta Magazine, "Solution: ‘Is Infinity Real?’," 30 June 2016 The researchers first used a tiny glass needle, its tip measuring only 10 microns across, to inject a single droplet of ferromagnetic fluid between the embryo’s cells. Quanta Magazine, "‘Traffic Jams’ of Cells Help to Sculpt Embryos," 27 Sep. 2018 Not only does this add flexibility in what can be studied, the plane of study shrunk down to three microns. David Grossman, Popular Mechanics, "These Glowing Fruit Fly Heads Can Help Us Understand the Human Brain," 26 Nov. 2018 And fine particulates, classified as 2.5 microns or less in diameter, are just one type of pollution. Umair Irfan, Vox, "How improving air quality could add years to people’s lives around the world.," 21 Nov. 2018

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 2019

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Time Traveler for micron

The first known use of micron was in 1879

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More Definitions for micron


mi·​cron | \ ˈmī-ˌkrän How to pronounce micron (audio) \

Medical Definition of micron

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

called also micrometer, mu

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More from Merriam-Webster on micron

Rhyming Dictionary: Words that rhyme with micron

Spanish Central: Translation of micron

Nglish: Translation of micron for Spanish Speakers

Britannica.com: Encyclopedia article about micron

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