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
This process erodes a bit under 25 micrometers of the rock's surface before ending at 0.05 microseconds when the radiation from the Z machine fades out. John Timmer, Ars Technica, 24 Sep. 2024 Samples from eight of the cadavers contained microplastics — tiny bits of plastic that ranged from 5.5 micrometers to 26.4 micrometers in size. Kaitlin Sullivan, NBC News, 16 Sep. 2024 Sixteen plastic fibers and particles were found in the eight brains and ranged from 5.5 micrometers—smaller than the diameter of a human red blood cell—to 26.4 micrometers in size. Ty Roush, Forbes, 16 Sep. 2024 Unable to see the smallest particles The new study, published Monday in the journal JAMA Network Open, found microplastics in the olfactory bulbs of eight of 15 cadavers that ranged in size from 5.5 micrometers, or 0.000217 of an inch, to 26.4 micrometers, or 0.001039 of an inch. Sandee Lamotte, CNN, 16 Sep. 2024 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

Dictionary Entries Near micrometer

Cite this Entry

“Micrometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/micrometer. Accessed 24 Nov. 2024.

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
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
: micron

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