mi·​cro·​gram | \ ˈmī-krə-ˌgram How to pronounce microgram (audio) \

Definition of microgram

: one millionth of a gram — see Metric System Table

Examples of microgram in a Sentence

Recent Examples on the Web

Lawyers say up to 100 micrograms of the synthetic opioid would be normal for a patient, depending on their size and the circumstances. NBC News, "Ohio doctor charged with 25 counts of murder, accused of prescribing excessive doses of painkillers," 5 June 2019 In other cases, patients were given doses exceeding 500 micrograms of fentanyl. NBC News, "Ohio doctor charged with 25 counts of murder, accused of prescribing excessive doses of painkillers," 5 June 2019 The murder charges were brought only in cases that involved fentanyl doses of at least 500 micrograms. Kantele Franko, Anchorage Daily News, "Ohio doctor accused of murder in 25 patient overdose deaths," 6 June 2019 In Seeley Lake, the particulate levels were routinely in excess of 300 micrograms per cubic liter. Marc Peruzzi, Outside Online, "Wildfire Smoke Is Here to Stay," 5 June 2019 The researchers found that, overall, IUDs containing 52 micrograms of levonorgestrel (that would be Mirena and Liletta—the others contain less of the hormone) seemed to be similarly effective at seven years as at three and five. Korin Miller, SELF, "When Is It OK to Get Your IUD Removed?," 12 Mar. 2019 The average levels in urine had more than doubled in two decades, from 0.203 micrograms per liter (µg/L) in 1993-1996 to 0.449 µg/L in 2014-2016. Matthew Berger, Fox News, "Can using weed killer give you cancer?," 27 Aug. 2018 For instance, tests at the district’s Academy of the Americas Elementary school found a kitchen and drinking faucet in a basement cafeteria that had lead levels of 182 micrograms per liter (ug/L) and 154 ug/L, respectively. Beth Mole, Ars Technica, "Lead in US school water “disturbing”—Detroit just shut off all fountains," 31 Aug. 2018 All women of reproductive age — but especially Hispanic women — should eat only fortified corn products and take daily supplements that contain 400 micrograms of folic acid, the researchers said. Jonel Aleccia, The Seattle Times, "FDA allows food makers to fortify corn masa to halt birth defects, but few do," 16 Oct. 2018

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

circa 1890, in the meaning defined above

History and Etymology for microgram

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Statistics for microgram

Last Updated

8 Jul 2019

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Time Traveler for microgram

The first known use of microgram was circa 1890

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More Definitions for microgram


mi·​cro·​gram | \ ˈmī-krə-ˌgram How to pronounce microgram (audio) \

Medical Definition of microgram

1 : one millionth of a gram

More from Merriam-Webster on microgram

Britannica.com: Encyclopedia article about microgram

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an act or instance of editing or removing

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