unit

1 of 2

noun

1
a
: the first and least natural number : one
b
: a single quantity regarded as a whole in calculation
2
: a determinate quantity (as of length, time, heat, or value) adopted as a standard of measurement: such as
a
: an amount of work used in education in calculating student credits
b
: an amount of a biologically active agent (such as a drug or antigen) required to produce a specific result see also international unit
3
a
: a single thing, person, or group that is a constituent of a whole
b
: a part of a military establishment that has a prescribed organization (as of personnel and matériel)
c
: a piece or complex of apparatus serving to perform one particular function
d
: a part of a school course focusing on a central theme
e
: a local congregation of Jehovah's Witnesses
f
: a small molecule especially when combined in a larger molecule
repeating units of a polymer
g
: an area in a medical facility and especially a hospital that is specially staffed and equipped to provide a particular type of care
an intensive care unit

unit

2 of 2

adjective

: being, relating to, or measuring one unit

Examples of unit in a Sentence

Noun The family is the basic unit of society. The search party broke up into smaller units. Their army unit guarded the border. Feet and meters are units of length. The dollar is the principal unit of American currency.
Recent Examples on the Web
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Noun
Weaver believes the unit is benefiting tremendously from working against a star wide receiver tandem of Tyreek Hill and Jaylen Waddle. David Furones, Sun Sentinel, 4 Aug. 2025 Even though Motorola assembled Moto X units sold in the US in Texas, components like the battery, screen and motherboard were sourced from suppliers in Asia, according to Woodside. Lisa Eadicicco, CNN Money, 4 Aug. 2025 The Eagan Police Department has Grappler units attached to two of its Chevrolet Tahoe SUVs. Kathryn Kovalenko, Twin Cities, 4 Aug. 2025 After turning the unit on at the medium setting, the humidity was cut to 45 percent in just three minutes. Clint Davis, People.com, 4 Aug. 2025 See All Example Sentences for unit

Word History

Etymology

Noun

back-formation from unity

First Known Use

Noun

1570, in the meaning defined at sense 1a

Adjective

1633, in the meaning defined above

Time Traveler
The first known use of unit was in 1570

Browse Nearby Words

Cite this Entry

“Unit.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unit. Accessed 14 Aug. 2025.

Kids Definition

unit

1 of 2 noun
1
a
: the first and smallest natural number : one
b
: a single quantity regarded as a whole in calculation
2
: a definite quantity (as of length, time, or value) used as a standard of measurement
the dollar is the unit of U.S. money
3
a
: a single thing or person or group that is a part of a whole
b
: a part or arrangement of parts performing one function
a train drawn by two diesel units
c
: a part of a school course with a central theme

unit

2 of 2 adjective
: being, relating to, or measuring one unit of
unit length
unit angle

Medical Definition

unit

noun
1
: an amount of a biologically active agent (as a drug or antigen) required to produce a specific result under strictly controlled conditions
a unit of penicillin
see international unit
2
: a small molecule especially when combined in a larger molecule
repeating units of a polymer
3
: an area in a medical facility and especially a hospital that is specially staffed and equipped to provide a particular type of care
an intensive care unit

More from Merriam-Webster on unit

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