me·​ter-ki·​lo·​gram-sec·​ond ˈmē-tər-ˈki-lə-ˌgram-ˈse-kənd How to pronounce meter-kilogram-second (audio)
: of, relating to, or being a system of units using the meter, kilogram, and second as its base units
abbreviation mks

Note: The meter-kilogram-second system of units has largely been replaced with the International System of Units, which uses many of the same fundamental quantities to derive its units but is more rigorously defined and overseen.

Word History

First Known Use

1888, in the meaning defined above

Time Traveler
The first known use of meter-kilogram-second was in 1888

Dictionary Entries Near meter-kilogram-second

Cite this Entry

“Meter-kilogram-second.” Dictionary, Merriam-Webster, Accessed 1 Apr. 2023.

Kids Definition


: of, relating to, or being a system of units based on the meter as the unit of length, the kilogram as the unit of mass, and the second as the unit of time

Medical Definition


variants or chiefly British metre-kilogram-second also metre-kilogramme-second
: mks
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