micrometer

1 of 2

noun (1)

mi·​crom·​e·​ter mī-ˈkrä-mə-tər How to pronounce micrometer (audio)
1
: an instrument used with a telescope or microscope for measuring minute distances
2
: a caliper for making precise measurements that has a spindle moved by a finely threaded screw

Illustration of micrometer

Illustration of micrometer
  • micrometer 2

micrometer

2 of 2

noun (2)

mi·​cro·​me·​ter ˈmī-krō-ˌmē-tər How to pronounce micrometer (audio)
: a unit of length equal to one millionth of a meter

called also micron

see Metric System Table

Examples of micrometer 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.
Noun
Researchers identified 5 micrometers as the optimal diameter for balancing bandwidth and power consumption. — Aamir Khollam, Interesting Engineering, 30 Oct. 2026 Within the ribbons, the team also embedded 470-micrometer-long strips of a piezoelectric ceramic material, lead zirconate titanate. — Edd Gent, IEEE Spectrum, 29 Oct. 2026 The device reproduced the fingerprint's tiny ridges and valleys, demonstrating an impressive spatial resolution of 30 micrometers (847 dpi). — New Atlas, 27 Oct. 2026 Twelve-micrometer polystyrene films got punched through while 130-micrometer films survived. — Jacek Krywko, ArsTechnica, 31 Aug. 2026 See All Example Sentences for micrometer

Word History

Etymology

Noun (1)

French micromètre, from micr- + -mètre -meter

Noun (2)

International Scientific Vocabulary micr- + meter entry 3

First Known Use

Noun (1)

1670, in the meaning defined at sense 1

Noun (2)

1880, in the meaning defined above

Time Traveler
The first known use of micrometer was in 1670

Rhymes for micrometer

See All Rhymes for micrometer

Browse Nearby Words

micrometeorology
micrometer
micrometer caliper
See all Nearby Words

Cite this Entry

“Micrometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/micrometer. Accessed 1 Nov. 2026.

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Kids Definition

micrometer

1 of 2 noun
mi·​crom·​e·​ter mī-ˈkräm-ət-ər How to pronounce micrometer (audio)
1
: an instrument used with a telescope or microscope for measuring very small distances
2
: micrometer caliper
micrometry
-ˈkräm-ə-trē
noun

micrometer

2 of 2 noun
mi·​cro·​me·​ter ˈmī-krō-ˌmēt-ər How to pronounce micrometer (audio)
: a unit of length equal to one millionth of a meter

Medical Definition

micrometer

1 of 2 noun
mi·​crom·​e·​ter mī-ˈkräm-ət-ər How to pronounce micrometer (audio)
: an instrument used with a telescope or microscope for measuring minute distances

micrometer

2 of 2 noun
mi·​cro·​me·​ter
variants or chiefly British micrometre
ˈmī-krō-ˌmēt-ər How to pronounce micrometer (audio)
: micron

More from Merriam-Webster on micrometer

Britannica.com: Encyclopedia article about micrometer

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