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.
Engineers used advanced steel-concrete composite techniques and deployed some of the largest cranes to position components with millimeter precision. Kaif Shaikh, Interesting Engineering, 3 Oct. 2025 Luigi Avantaggiato PacBio’s Wenger notes that the 25-million-well chips that underpin its Revio system are still being fabricated on 200-millimeter semiconductor wafers. IEEE Spectrum, 2 Oct. 2025 According to the complaint, both Collins and Robledo carried 9-millimeter semiautomatic pistols to the protests and have lawful permits for the weapons. Bill Kirkos, CNN Money, 29 Sep. 2025 But da Costa and his team, as part of the Microns project, a large-scale effort to fully map out a 1-cubic-millimeter portion of a mouse’s visual cortex, discovered that inhibitory neurons are very specific in choosing what cells to inhibit. Yasemin Saplakoglu, Quanta Magazine, 29 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 5 Oct. 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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