mil·​li·​me·​ter | \ ˈmi-lə-ˌmē-tər How to pronounce millimeter (audio) \
variants: or British millimetre

Definition of millimeter

: a unit of length equal to ¹/₁₀₀₀ meter — see Metric System Table

Examples of millimeter in a Sentence

Recent Examples on the Web

Sure enough, the crew members traced the problem to a hole about two millimeters wide in one of the visiting Soyuz capsules, which is the vehicle used to transport astronauts to and from the station. Loren Grush, The Verge, "Russian cosmonauts are spacewalking to figure out the origin of a mysterious spacecraft hole," 11 Dec. 2018 At its most delicate, the concrete slab is just 20 millimeters thick, which has both aesthetic and functional benefits. Liz Stinson, Curbed, "Cool rippling concrete ceiling was made with 3D printing," 7 Aug. 2018 Gilman was shot in the back; the bullet punctured a lung, lacerated her spleen and a kidney, broke two ribs and lodged 2 millimeters from her spinal cord. Fox News, "Living with fear: Vegas shooting survivor, wife march on," 27 Sep. 2018 Malignant moles tend to have asymmetrical or irregular borders, uneven color, a diameter greater than six millimeters, and/or a rapidly changing appearance. Allure, "The Skin-Care Glossary: A Comprehensive Guide to Everything You Need to Know," 17 Aug. 2018 Another clue indicating the level of micromanagement in the summit’s planning: The table between the leaders measures exactly 2018 millimeters. Washington Post, "Korean leaders seek to control optics at historic summit," 25 Apr. 2018 Using several layers of epoxy resin, astronauts inside the space station patched the slow leak—from a small hole a few millimeters across—a day after its detection. Eric Berger, Ars Technica, "Russian cosmonauts spend nearly eight hours cutting into their spacecraft," 12 Dec. 2018 That’s about the same weight as the 3rd Gen X1 Yoga, but the footprint has shrunk by about half an inch in its length and width, and a couple of millimeters in thickness, too. Mark Hachman, PCWorld, "Lenovo's ThinkPad X1 Carbon, X1 Yoga slim down with 8th-gen Core chips for 2019," 7 Jan. 2019 The end result is a gyroscope that is only a couple of square millimeters. Chris Lee, Ars Technica, "Awesome tiny gyroscope promising but not ready for prime time," 9 Nov. 2018

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

1797, in the meaning defined above

History and Etymology for millimeter

French millimètre, from milli- + mètre meter

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Statistics for millimeter

Last Updated

12 Mar 2019

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Time Traveler for millimeter

The first known use of millimeter was in 1797

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English Language Learners Definition of millimeter

: a length equal to 1/1000 meter


mil·​li·​me·​ter | \ ˈmi-lə-ˌmē-tər How to pronounce millimeter (audio) \

Kids Definition of millimeter

: a unit of length equal to 1/1000 meter


variants: or chiefly British millimetre \ ˈmil-​ə-​ˌmēt-​ər How to pronounce millimetre (audio) \

Medical Definition of millimeter

: one thousandth of a meter abbreviation mm

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Rhyming Dictionary: Words that rhyme with millimeter

Spanish Central: Translation of millimeter

Nglish: Translation of millimeter for Spanish Speakers

Britannica English: Translation of millimeter for Arabic Speakers

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What made you want to look up millimeter? Please tell us where you read or heard it (including the quote, if possible).


grandiloquent, ostentatious, or bombastic

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