millimeter

noun

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The patina in some areas is over a millimeter thick. Theo Burman, MSNBC Newsweek, 12 Sep. 2025 The 42mm models have 374-by-446 screens with 989 square millimeters of display area, and the 46mm ones are 416 by 496 with 1,220mm^2. PC Magazine, 10 Sep. 2025 Without that access, startups and researchers won’t be able to afford to do relevant work using 300-millimeter wafers and advanced chip-technology nodes. IEEE Spectrum, 10 Sep. 2025 The latter, which are millimeter-size blobs, are each surrounded by black rings that scientists determined contain iron and phosphate after studying them with Perseverance's toolkit. Monisha Ravisetti, Space.com, 10 Sep. 2025 See All Example Sentences for millimeter

Word History

Etymology

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

Browse Nearby Words

Cite this Entry

“Millimeter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/millimeter. Accessed 15 Sep. 2025.

Kids Definition

millimeter

noun
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

millimeter

noun
mil·​li·​me·​ter
variants or chiefly British millimetre
: one thousandth of a meter
abbreviation mm

More from Merriam-Webster on millimeter

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