micrometer

1 of 2

noun (1)

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

Illustration of micrometer

• micrometer 2

micrometer

2 of 2

noun (2)

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 Table

Examples of micrometer in a Sentence

Recent Examples on the Web

Noun

Nanoplastics are much tinier, smaller than 1 micrometer, roughly 1/80th to 1/100th the width of a human hair. — Tom Gavin, EverydayHealth.com, 15 July 2026

Microscale printing advances Using the technique, the team fabricated microtubule arrays with individual tube diameters as small as 6 micrometers. — Neetika Walter, Interesting Engineering, 10 July 2026

The joining pads must be precisely aligned to within less than a micrometer for the process to work. — Alex Music, IEEE Spectrum, 25 June 2026

Previous research shows speeds reaching 120 micrometers a second. — Andrew Paul, Popular Science, 11 June 2026

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

Rhymes for micrometer

• barometer
• chronometer
• geometer
• hydrometer
• hygrometer
• kilometer
• odometer
• photometer
• psychrometer
• pycnometer
• pyrometer
• rheometer

Kids 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

2

: micrometer caliper

micrometry

-ˈkräm-ə-trē

noun

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

micrometer

2 of 2 noun

mi·​cro·​me·​ter

variants or chiefly British micrometre

ˈmī-krō-ˌmēt-ər 

: micron