density

American  

[den-si-tee] / ˈdɛn sɪ ti /

noun

densities plural

1. the state or quality of being dense; compactness; closely set or crowded condition.

2. stupidity; slow-wittedness; obtuseness.

3. the number of inhabitants, dwellings, or the like, per unit area.

   The commissioner noted that the population density of certain city blocks had fallen dramatically.

4. Physics. mass per unit volume.

5. Electricity.

   1. the quantity of electricity per unit of volume at a point in space, or the quantity per unit of area at a point on a surface.

   2. current density.

6. the degree of opacity of a substance, medium, etc., that transmits light.

7. Photography. the relative degree of opacity of an area of a negative or transparency, often expressed logarithmically.

8. Computers. a measure of the compactness of data saved on a storage medium, as disk or tape, or displayed on an electronic screen.

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density British  

/ ˈdɛnsɪtɪ /

noun

1. the degree to which something is filled, crowded, or occupied

   high density of building in towns

2. obtuseness; stupidity

3.  ρ.  a measure of the compactness of a substance, expressed as its mass per unit volume. It is measured in kilograms per cubic metre or pounds per cubic foot See also relative density

4. a measure of a physical quantity per unit of length, area, or volume See charge density current density

5. physics photog See transmission density reflection density

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density Scientific  

/ dĕn′sĭ-tē /

1. A measure of the quantity of some physical property (usually mass) per unit length, area, or volume (usually volume).

2. ◆ Mass density is a measure of the mass of a substance per unit volume. Most substances (especially gases such as air) increase in density as their pressure is increases or as their temperature decreases.

3. ◆ Energy density is a measure of the amount of energy (often in the form of electromagnetic radiation) per unit volume in a region of space or some material.

4. See also Boyle's law

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density Cultural  

1. The relative heaviness of objects, measured in units of mass or weight per units of volume. (See specific gravity.)

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Other Word Forms

Derived Forms

• nondensity
  noun
• superdensity
  noun

Inflected Forms

Nouns

• densities
  plural

Etymology

Origin of density

First recorded in 1595–1605; from Latin dēnsitās, equivalent to dēns(us) dense + -itās -ity

Explanation

Density describes how compact or concentrated something is. For example, suppose you have two boxes, one large and one small. However, they both weigh the same. That means the small box has a higher density than the large box. Density also tells how concentrated or crowded something is. You may have heard of population density. In a city, there are many people packed into a small area, giving it a high population density. In a rural area, there are more fields or wooded areas between houses. That means there are fewer people living in a larger area, which is why it has a low population density.

Example Sentences

In other words, L.A. will allow a little more density, but not as much as SB 79 calls for.

From Los Angeles Times • Jul. 1, 2026

"What is absolutely amazing here is the sheer density of people who inevitably have something to offer when you set out to start a business."

From Barron's • Jul. 1, 2026

The comparison becomes even more striking when measured against candy floss, which has a typical density of about 0.05 grams per cubic centimeter.

From Science Daily • Jun. 27, 2026

"It never ceases to amaze me how the density of the informational ecosystem was at the time".

From BBC • Jun. 27, 2026

Within the last 5,000 years, some of those productive regions witnessed an intensification of Aboriginal food-gathering methods, and a buildup of Aboriginal population density.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

Related Words

• frequency
• quantity
• thickness