density

UK: /ˈdɛnsɪti/ US: /ˈdɛnsɪti/ ,(den′si tē)

Inflections of 'density' (n): npl: densities

WordReference Random House Learner's Dictionary of American English © 2025

den•si•ty /ˈdɛnsɪti/   n., pl. -ties. 

1. the state or quality of being dense:
   [uncountable] the density of the prose.
2. the average number of inhabitants per unit of area:
   [countable] a population density of 100 persons per square mile.
3. Physics the relation of mass to volume;
   mass per unit volume:
   [countable] a density of 15 cubic centimeters per gram.
4. Computing a measure of how much data can be stored in a given amount of space on a disk, tape, or other computer storage medium:
   [uncountable] a high-density disk.
5. [uncountable] great stupidity or dullness.

WordReference Random House Unabridged Dictionary of American English © 2025

den•si•ty  (den′si tē), n., pl. -ties. 

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
   • 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.
   • See current density. 
6. Optics 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. Computing a measure of the compactness of data stored on an external storage medium, as disk or tape, or displayed on a CRT or other screen.

• Latin dēnsitās, equivalent. to dēns(us) dense + -itās -ity
• 1595–1605

Collins Concise English Dictionary © HarperCollins Publishers::

density / ˈdɛnsɪtɪ/ noun ( -ties)

1. the degree to which something is filled, crowded, or occupied: high density of building in towns
2. obtuseness; stupidity
3. 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
   Symbol: ρ
   See also relative density
4. a measure of a physical quantity per unit of length, area, or volume
5. See transmission density, reflection density