mil·​li·​gram | \-ˌgram \

Definition of milligram 

: a unit of mass equal to ¹/₁₀₀₀ gram — see Metric System Table

Examples of milligram in a Sentence

Recent Examples on the Web

In some cases, as little as 0.3 to 0.5 milligrams is enough. Emily Sohn, Washington Post, "Time-zone changes can leave people worried about jet lag," 7 July 2018 At the start, the patients had allergic reactions to no more than 100 milligrams of peanut protein, equivalent to one-third of a peanut kernel. Peter Loftus, WSJ, "Experimental Drug Shows Promise Protecting Against Peanut Allergies," 18 Nov. 2018 But, as the Kansas City Star reported, that amount of fentanyl would contain enough lethal doses to potentially kill more than 26 million people, given that the DEA says as little as 2 milligrams can be fatal. Lindsey Bever, Washington Post, "Inside a truck in Nebraska, troopers found enough fentanyl to kill millions of people," 25 May 2018 An 8-ounce cup of coffee usually has about 95 milligrams of caffeine, but a lot of cold brews are sold in a concentrated form that needs to be diluted with water. Audrey Bruno, SELF, "10 Dietitian-Approved Iced Coffees and Cold Brews You Can Buy at the Supermarket," 9 May 2018 Hayes found that four-foot snakes injected close to 100 milligrams into the mice. Kyle Dickman, Outside Online, "A Rattle with Death in Yosemite," 20 June 2018 Most healthy adults can consume up to 400 milligrams (mg) of caffeine–the amount in approximately four cups of regular coffee–per day. Tori Rodriguez, Woman's Day, "5 "Bad" Habits That Are Actually Good for You," 3 Aug. 2016 Experts say just a few milligrams of the odorless Novichok liquid — the weight of a snowflake — is enough to kill a person within minutes. Matt Dunham And Gregory Katz,, "British police race to find source of new nerve agent poisoning," 6 July 2018 Gillespie says the typical cup of drip coffee has 100 to 200 milligrams of caffeine. Ac Shilton, Outside Online, "Coffees That Deliver on Twice the Caffeine," 25 May 2018

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

1797, in the meaning defined above

History and Etymology for milligram

French milligramme, from milli- + gramme gram

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Statistics for milligram

Last Updated

12 Dec 2018

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Time Traveler for milligram

The first known use of milligram was in 1797

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More Definitions for milligram



English Language Learners Definition of milligram

: a weight equal to 1/1000 gram


mil·​li·​gram | \ˈmi-lə-ˌgram \

Kids Definition of milligram

: a unit of weight equal to 1/1000 gram


variants: or chiefly British milligramme \-​ˌgram \

Medical Definition of milligram 

: one thousandth of a gram abbreviation mg

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More from Merriam-Webster on milligram

Rhyming Dictionary: Words that rhyme with milligram

Spanish Central: Translation of milligram

Nglish: Translation of milligram for Spanish Speakers

Britannica English: Translation of milligram for Arabic Speakers Encyclopedia article about milligram

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