mil·​li·​me·​ter | \ˈmi-lə-ˌmē-tər \
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

Additionally, Intel says that the modem will support both millimeter wave (mmWave) spectrum as well as lower-band parts of the spectrum. Chaim Gartenberg, The Verge, "Intel’s new 5G modem might power Apple’s first 5G iPhones," 12 Nov. 2018 That means the mole is asymmetrical, has an irregular border, is made up of different nonuniform shades of color, has a diameter larger than 6 millimeters across, or is evolving and changing in shape, size or color. Korin Miller, SELF, "'DWTS' Star Witney Carson's Foot Discoloration Turned Out to Be Melanoma," 24 Aug. 2018 The millimeter wave radar helps the weapon detect and track targets through the adverse weather. Allison Barrie, Fox News, "StormBreaker: Powerful bomb penetrates bad weather, spells bad news for bad guys," 27 July 2018 Although West Antarctica contributed just 6 millimeters of sea level rise in that time, scientists say ice-sheet collapse there could raise global sea levels by 3 meters in the coming centuries. Katie Langin, Science | AAAS, "Rising bedrock below West Antarctica could delay catastrophic ice sheet collapse," 21 June 2018 Needless to say, each lamp would die after a single flash, so it was designed in a form of bullet with a caliber of 10 millimeters, which would be loaded from a cartridge containing eight shots. Anatoly Zak, Popular Mechanics, "The Soviet Laser Space Pistol, Revealed," 14 June 2018 That puts the grain diameter at 0.2 to 0.3 millimeters—the size of an average sand grain on Earth. Scott K. Johnson, Ars Technica, "Frozen Pluto has wind-blown dunes made of methane sand," 31 May 2018 Instead, this tiny beetle -- only 1.5 millimeters long -- lives alongside a species of nomadic army ant. Ashley Strickland, CNN, "Meet the top 10 new species of 2018," 23 May 2018 Instead of stitching the hipbelt to the back panel, Kelty feeds it behind the lumbar pad and allows it a few millimeters of movement, as if each wing of the hipbelt were a playground teeter-totter. Kelly Bastone, Outside Online, "The Best Women’s Backpacking Packs," 13 July 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

19 Nov 2018

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Time Traveler for millimeter

The first known use of millimeter was in 1797

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More Definitions for millimeter



English Language Learners Definition of millimeter

: a length equal to 1/1000 meter


mil·​li·​me·​ter | \ˈmi-lə-ˌmē-tər \

Kids Definition of millimeter

: a unit of length equal to 1/1000 meter


variants: or chiefly British millimetre \ˈmil-​ə-​ˌmēt-​ər \

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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to enclose within walls

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