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
Feet and meters are both units of length.
: 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
The family is the basic units of society.
The search party broke up into smaller units.
b
: a part of a military establishment that has a prescribed organization (as of personnel and matériel)
c(1)
: a piece or complex of apparatus serving to perform one particular function
an air conditioning unit
(2)
: a set of similar pieces of furniture that are grouped or attached together
a built-in storage/wall unit
(3)
: an individual item of the products that a company makes or sells
d
: a part of a school course focusing on a central theme
finished the unit on the American Revolution
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
h
: one of a number of apartment or residences in a building or complex

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
Defensively, Philadelphia has been one of the most disciplined units in the league, limiting big plays and forcing opponents into third-and-long situations. Ben Verbrugge, MSNBC Newsweek, 17 Nov. 2025 The third component has 60 units. Joseph Flaherty, Arkansas Online, 17 Nov. 2025 Seventeen residents were forced from their homes early Sunday after a fire moved through multiple units at a Roswell apartment complex, according to city fire officials. Cbs News Atlanta Digital Team, CBS News, 17 Nov. 2025 Military units will inspect some 75 miles of track running to the Polish town of Hrubieszow along the border with Ukraine, Kosiniak-Kamysz said. David Brennan, ABC News, 17 Nov. 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 19 Nov. 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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