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.
For instance, Quaise Energy has developed a millimeter-wave drilling technology that can vaporize rock using high-frequency electromagnetic waves rather than conventional drill bits. Georgina Jedikovska, Interesting Engineering, 10 Oct. 2025 For cinephiles, this feature, shot on 16-millimeter film, will likely feel like a successor to John Waters’ dynasty of filth, down to its setting in the fictional urban sprawl of Trashtown. Elaina Patton, NBC news, 9 Oct. 2025 Because of their history servicing the Navy, the watches are large, ranging from 38 millimeters to 47 millimeters, are rigorously tested to be water-resistant to as much as 500 meters, and are durable. Jean E. Palmieri, Footwear News, 9 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 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 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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