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.
Instead of producing individual flexible or transparent devices in the laboratory, their approach creates 300-millimeter wafers containing the optical structures needed for silicon photonics. — Neetika Walter, Interesting Engineering, 3 Sep. 2026 The drops slid about four centimeters, picked up a charge, rolled off the edge, and then fell five millimeters onto a copper plate coated with a 60-nanometer film of Teflon, which is one of the most chemically resistant coatings on the market today. — Jacek Krywko, ArsTechnica, 31 Aug. 2026 For a precision folding bike where millimeter-perfect alignment dictates how smoothly the hinges open and close, keeping the metal perfectly straight is a manufacturing advantage. — New Atlas, 29 Aug. 2026 This film finds a third-bowl-of-porridge option that lets the tall, stark, and handsome star channel both old-fashioned Hollywood strong, silent types and suggest strong undercurrents of pain running mere millimeters beneath the surface. — David Fear, Rolling Stone, 28 Aug. 2026 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

Rhymes for millimeter

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Browse Nearby Words

millime
millimeter
millimetric
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Cite this Entry

“Millimeter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/millimeter. Accessed 4 Sep. 2026.

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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
ˈmil-ə-ˌmēt-ər How to pronounce millimeter (audio)
: one thousandth of a meter
—abbreviation mm
Last Updated: - Updated example sentences
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