base unit

noun

plural base units
: one of a set of fundamental units in a system of measurement that is based on a natural phenomenon or established standard and from which other units may be derived
The base units of the International System of Units are the meter, kilogram, second, ampere, kelvin, mole, and candela.
compare absolute unit

Examples of base unit 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.
The landline base unit has two RJ-11 phone jacks at the rear, along with a hardwired power cord. — John R. Delaney, PC Magazine, 6 Apr. 2026 Russia was also able to connect the drone’s fiber-optic cable to a base unit, which was then linked to a drone operator. — Charbel Mallo, CNN Money, 3 May 2026 The horizontal base unit has five slots that can fit magnetically attachable modules. — Abhimanyu Ghoshal, New Atlas, 31 Oct. 2025 In an electrified economy where artificial intelligence is increasingly the driver of growth, the kilowatt-hour is the base unit. — Chase Weir, Forbes.com, 7 Apr. 2026 See All Example Sentences for base unit

Word History

First Known Use

1867, in the meaning defined above

Time Traveler
The first known use of base unit was in 1867

Rhymes for base unit

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Browse Nearby Words

base time
base unit
bash
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Cite this Entry

“Base unit.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/base%20unit. Accessed 7 Jul. 2026.

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Medical Definition

base unit

noun
: one of a set of simple units in a system of measurement that is based on a natural phenomenon or established standard and from which other units may be derived see international system of units
Last Updated: - Updated example sentences
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