mil·​li·​me·​ter ˈmi-lə-ˌmē-tər How to pronounce millimeter (audio)
variants US millimeter or British millimetre
: a unit of length equal to ¹/₁₀₀₀ meter see Metric System Table

Examples of millimeter in a Sentence

Recent Examples on the Web Most of the time, these sensors track very slow movement, on the order of millimeters or less per year. Rong-Gong Lin Ii, Los Angeles Times, 5 June 2024 Shield did not detect small lesions of less than 10 millimeters. Mary Kekatos, ABC News, 24 May 2024 When shopping for compression socks, podiatrist Salma Aziz, DPM, MS, says pregnant people should start with a mild compression of 15-20 millimeters of mercury (mmHg). Laura Lu, Ms, Parents, 21 May 2024 Scanning each of these targets took eight minutes or less for image resolutions of roughly 2 by 2 by 8 cubic millimeters. IEEE Spectrum, 15 May 2024 See all Example Sentences for millimeter 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'millimeter.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


French millimètre, from milli- + mètre meter

First Known Use

1797, in the meaning defined above

Time Traveler
The first known use of millimeter was in 1797

Dictionary Entries Near millimeter

Cite this Entry

“Millimeter.” Dictionary, Merriam-Webster, Accessed 13 Jun. 2024.

Kids Definition


mil·​li·​me·​ter ˈmil-ə-ˌmēt-ər How to pronounce millimeter (audio)
: a measure of length equal to ¹⁄₁₀₀₀ meter see metric system table

Medical Definition


variants or chiefly British millimetre
: one thousandth of a meter
abbreviation mm

More from Merriam-Webster on millimeter

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