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 Each participant received 10, 30, or 100 microgram doses of the vaccine or a placebo. Cassidy Morrison, Washington Examiner, "Pfizer coronavirus vaccine candidate shows early promise," 1 July 2020 Moderna initially tested several different doses of the vaccine in volunteers, but will use a 100 microgram dose in the final trial. NBC News, "Coronavirus vaccine: Human trials advance, Army selects top drug candidate," 12 June 2020 The vaccine, known as mRNA-1273, will be given in the 100 microgram dose level in the trial, which is being done in conjunction with the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health. Fox News, "Moderna's enormous coronavirus vaccine Phase III trial will start next month," 11 June 2020 What has not been revealed Unconventional for a scientific study, data was given from only eight of the 45 volunteers — four each from the 25 and 100 microgram doses, who developed neutralizing antibodies. Sanjay Mishra, The Conversation, "What the phase 1 trials of the first COVID-19 vaccine really mean," 21 May 2020 Three participants experience flu-like symptoms after receiving a second vaccination at a 250 microgram dose, the highest included in the phase one trial. Mirel Zaman, refinery29.com, "Moderna’s Coronavirus Vaccine Is Looking Promising," 19 May 2020 The n = 8 thing The company’s statement led with the fact that all 45 subjects (in this analysis) who received doses of 25 micrograms (two doses each), 100 micrograms (two doses each), or a 250 micrograms (one dose) developed binding antibodies. Helen Branswell, STAT, "Vaccine experts say Moderna didn’t produce data critical to assessing Covid-19 vaccine," 19 May 2020 But because the early data shows that the lower doses (25 micrograms and 100 micrograms) were so effective, the researchers are dropping the highest dose from its next trials. Mirel Zaman, refinery29.com, "Moderna’s Coronavirus Vaccine Is Looking Promising," 19 May 2020 So far, the Moderna study subjects who were vaccinated even at 25 and 100 micrograms achieved antibody levels similar to or even higher than people who naturally became infected with coronavirus. Elizabeth Cohen, CNN, "Early results from Moderna coronavirus vaccine trial show participants developed antibodies against the virus," 18 May 2020

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

International Scientific Vocabulary

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Time Traveler for microgram

Time Traveler

The first known use of microgram was circa 1890

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Statistics for microgram

Last Updated

13 Jul 2020

Cite this Entry

“Microgram.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microgram. Accessed 15 Jul. 2020.

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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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