unit

¹ American  

[yoo-nit] / ˈyu nɪt /

noun

1. a single thing or person.

2. any group of things or persons regarded as an entity.

   They formed a cohesive unit.

3. one of the individuals or groups that together constitute a whole; one of the parts or elements into which a whole may be divided or analyzed.

4. one of a number of things, organizations, etc., identical or equivalent in function or form.

   a rental unit;

   a unit of rolling stock.

5. any magnitude regarded as an independent whole; a single, indivisible entity.

6. Also called dimension.  any specified amount of a quantity, as of length, volume, force, momentum, or time, by comparison with which any other quantity of the same kind is measured or estimated.

7. the least positive integer; one.

8. Also called unit's place. 

   1. (in a mixed number) the position of the first digit to the left of the decimal point.

   2. (in a whole number) the position of the first digit from the right of the decimal point.

9. a machine, part, or system of machines having a specified purpose; apparatus.

   a heating unit.

10. Education. a division of instruction centering on a single theme.

11. Military. an organized body of soldiers, varying in size and constituting a subdivision of a larger body.

12. Medicine/Medical.

    1. the measured amount of a substance necessary to cause a certain effect; a clinical quantity used when a substance cannot be readily isolated in pure form and its activity determined directly.

    2. the amount necessary to cause a specific effect upon a specific animal or upon animal tissues.

13. Mathematics.

    1. an identity element.

    2. an element in a group, ring, etc., that possesses an inverse.

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Unit. ² American  

abbreviation

1. Unitarian.

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unit ¹ British  

/ ˈjuːnɪt /

noun

1. a single undivided entity or whole

2. any group or individual, esp when regarded as a basic element of a larger whole

3. a mechanical part or integrated assembly of parts that performs a subsidiary function

   a filter unit

4. a complete system, apparatus, or establishment that performs a specific function

   a production unit

5. a subdivision of a larger military formation

6. Also called: unit of measurement.  A standard amount of a physical quantity, such as length, mass, energy, etc, specified multiples of which are used to express magnitudes of that physical quantity

   the second is a unit of time

7. the amount of a drug, vaccine, etc, needed to produce a particular effect

8. a standard measure used in calculating alcohol intake and its effect

9. maths

   1. (usually plural) the first position in a place-value counting system, representing a single-digit number

      in the decimal system the number 27 has 7 units and 2 tens

   2. (modifier) having a value defined as one for the system

      unit vector

10. Also called: unit set.  maths logic a set having a single member

11. short for home unit

12. short for stock unit

13. a self-propelled railcar

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Unit. ² British  

abbreviation

1. Unitarian

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Other Word Forms

• interunit adjective
• multiunit adjective
• subunit noun
• superunit noun

Etymology

Origin of unit

Coined in 1570 by John Dee ( def. ) as a translation of Greek mónas (previously rendered as unity ); perhaps influenced by digit

Example Sentences

Border Patrol agents from an elite unit rappelled from a hovering Black Hawk helicopter onto the roof of a 130-unit apartment complex.

From Salon • Apr. 6, 2026

Rising oil prices could boost the company’s 2026 full-year gas price to $6.00 per metric million British thermal unit from $5.7/mmBtu forecast previously, the analyst says.

From The Wall Street Journal • Apr. 6, 2026

Property records show that the unit is still registered to the limited liability company that Jackman and Furness used when they purchased the home in 2008.

From MarketWatch • Apr. 6, 2026

A deal revision allowed Microsoft to pursue superintelligence, leading Mustafa Suleyman to launch a new AI unit in November.

From Barron's • Apr. 4, 2026

By about 9:00 P.M., the water in unit 1 had boiled down to below the tops of the reactor’s fuel rods, and they were most likely already melting.

From "Meltdown" by Deirdre Langeland

Related Words

• crew
• entity
• group
• system