Illustration of micrometer
- micrometer 2
mi·crom·e·ter
mī-ˈkrä-mə-tər 
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
mi·cro·me·ter
ˈmī-krō-ˌmē-tər
: a unit of length equal to one millionth of a meter
called also micron
see Metric System TableExamples of micrometer in a Sentence
Recent Examples on the Web
Kristi Tanner, Freep.com, 13 July 2025
These particles are less than 2.5 micrometers in diameter – about a tenth the size of a pollen grain.
—John C. Quindry, The Conversation, 10 July 2025
The Environmental Protection Agency (EPA) has established air quality standards for two types: coarse particles (PM10), 10 micrometers or smaller, and fine particles (PM2.5), 2.5 micrometers or smaller.
—Joe Edwards, MSNBC Newsweek, 2 July 2025
Subsequent studies revealed a complex internal structure — an interwoven network of narrow tubes with diameters as small as 50 micrometers.
—Scott Travers, Forbes.com, 7 Apr. 2025
See All Example Sentences for micrometer
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Noun
Particles that are less than 10 micrometers and 2.5 micrometers in diameter are called PM10 and PM2.5, respectively.
—Kristi Tanner, Freep.com, 13 July 2025
These particles are less than 2.5 micrometers in diameter – about a tenth the size of a pollen grain.
—John C. Quindry, The Conversation, 10 July 2025
The Environmental Protection Agency (EPA) has established air quality standards for two types: coarse particles (PM10), 10 micrometers or smaller, and fine particles (PM2.5), 2.5 micrometers or smaller.
—Joe Edwards, MSNBC Newsweek, 2 July 2025
Subsequent studies revealed a complex internal structure — an interwoven network of narrow tubes with diameters as small as 50 micrometers.
—Scott Travers, Forbes.com, 7 Apr. 2025
See All Example Sentences for micrometer
Cite this Entry
“Micrometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/micrometer. Accessed 4 Aug. 2025.
Copy CitationKids Definition
micrometer
1 of 2 noun
mi·crom·e·ter
mī-ˈkräm-ət-ər
1
: an instrument used with a telescope or microscope for measuring very small distances
micrometry
noun
-ˈkräm-ə-trē
micrometer
2 of 2 noun
mi·cro·me·ter
ˈmī-krō-ˌmēt-ər
: 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
: an instrument used with a telescope or microscope for measuring minute distances
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