mi·​cro | \ ˈmī-(ˌ)krō How to pronounce micro (audio) \

Definition of micro

 (Entry 1 of 2)

1 : very small especially : microscopic
2 : involving minute quantities or variations


plural micros

Definition of micro (Entry 2 of 2)

Examples of micro in a Sentence

Recent Examples on the Web: Adjective

Arkin plans to sequence the genomes and select the seeds and micro-organisms that grow fastest and most effectively in space after testing them in chambers mimicking Mars’ atmosphere. Peter Fimrite, SFChronicle.com, "Long-term space journeys to allow humans to become almost completely self-sufficient," 8 June 2019 Sanjay Singhal, the founder of Audiobooks.com, is funding research into psilocybin and other psychedelics, including a planned study into micro-dosing at the University of Toronto’s Center for Psychedelic Studies. Bloomberg, The Mercury News, "First pot, then magic mushrooms? Decriminalization is spreading," 18 June 2019 Coral Vita uses a technique called micro-fragmentation which involves removing coral fragments from the ocean and breaking them into tiny pieces. Isabelle Gerretsen, CNN, "Can the world's first land-based coral farm save our reefs?," 13 June 2019 There is a micro-market where employees can find healthy snacks right inside the office. Leigh Farr, azcentral, "MEDIUM COMPANY RANKINGS:," 13 June 2019 Spend the final day in the hills outside Kigali, exploring three villages from the Millennium Villages Project, an initiative to reduce poverty that integrates health, education, and micro-enterprise. National Geographic, "Africa by Private Jet," 12 June 2019 The other thing the researchers looked at were micro-RNAs, or short sequences of RNA that regulate the activity of other genes. John Timmer, Ars Technica, "Why do bats have such bizarrely long lifespans?," 11 June 2019 How plant leaves, pollen and insects become fossils is more like what happens to marine micro-organisms. Anna K. Behrensmeyer, Smithsonian, "How Do Fossils Form?," 8 June 2019 Over the course of 55 experiments, Tajmar and his colleagues registered an average of 3.4 micro-Newtons of force from the EmDrive, which was very similar to what the NASA team found. Daniel Oberhaus, WIRED, "A Mythical Form of Space Propulsion Finally Gets a Real Test," 5 June 2019

Recent Examples on the Web: Noun

Portable chargers also often come with an included micro USB cable; iPhone users should use the lightning cable that came with their phone. Julianne Ross, CNN Underscored, "Over 20,000 people love these portable chargers," 2 July 2019 The big picture is harder to grasp while the micro blocks out the macro, though. Pat Brennan, Cincinnati.com, "Shorthanded FC Cincinnati looking to continue MLS progress at Minnesota United FC," 27 June 2019 The vegan, gluten-free-friendly Lime Green roll comes with micro greens Ikeda picks up in Tigard. Michael Russell, oregonlive.com, "Yoshi’s in Southwest Portland redefines food cart sushi," 21 June 2019 Another innovative program by a Chicago consulting firm, Parker Dewey, is an online micro-internship platform that links college students and recent grads with employers offering paid, short-term projects. Sue Shellenbarger, WSJ, "The Small-College Strivers Landing Big Jobs," 17 June 2019 Jack Dorsey is best known for co-founding Twitter, the micro-posting website that now has around 330 million users around the world. John Detrixhe, Quartz, "Jack Dorsey says now is our chance to build a global currency for the internet," 14 June 2019 Shared spaces and amenities increase human interaction and allow for smaller and micro-size homes. National Geographic, "Designing to scale: Resilient regions," 12 June 2019 The new red-carpet worry is cleavage lines For firming the jaw and neck and getting rid of tree trunk lines, radiofrequency micro-needling has taken over. Ingrid Schmidt, The Hollywood Reporter, "Derm-to-the-Stars Harold Lancer Says Big Butts Are Out, Lifted Nose Tips Are In," 27 June 2018 That’s topped with Cotswold pub cheese, micro-greens, pickles, housemade beets and Brussels sprouts sauerkraut, and a charred onion ketchup aioli that takes 24 hours to prepare. Pam Kragen, San Diego Union-Tribune, "Local chef’s ‘Psycho-Deli’ burger aims to change the way people eat," 20 June 2019

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


1923, in the meaning defined at sense 1


1971, in the meaning defined at sense 1

History and Etymology for micro



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Last Updated

7 Jul 2019

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The first known use of micro was in 1923

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More Definitions for micro


mi·​cro | \ ˈmī-(ˌ)krō How to pronounce micro (audio) \

Medical Definition of micro

1 : very small especially : microscopic
2 involving minute quantities or variations

More from Merriam-Webster on micro

Spanish Central: Translation of micro

Britannica English: Translation of micro for Arabic Speakers

Comments on micro

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characterized by aphorism

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