den·​si·​ty | \ ˈden(t)-sə-tē How to pronounce density (audio) \
plural densities

Definition of density

1 : the quality or state of being dense measures of traffic density the density of the cake felt that the candidate's density on the subject of equality was alarming the density of her prose
2 mathematics : the quantity per unit volume (see volume entry 1 sense 2), unit area (see area sense 1), or unit length: such as
a chemistry : the mass (see mass entry 2 sense 1c) of a substance per unit volume
b chemistry : the distribution of a quantity (such as mass, electricity, or energy) per unit usually of space (such as length, area, or volume)
c : the average number of individuals or units per space unit a population density of 500 per square mile a housing density of 10 houses per acre

3 physics

a : the degree of opacity (see opacity sense 2) of a translucent medium the fog's density
b : the common logarithm of the opacity

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Examples of density in a Sentence

We were surprised by the fog's density. the density of her writing style These instruments are used for measuring the density of the atmosphere.
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Recent Examples on the Web

Weight: Weight is an indicator of density, as it is measured by square foot. Lucia Tonelli, ELLE Decor, "The Best Carpet Types for a Perfectly Grounded Space," 13 Feb. 2019 All of the atoms in the planets, stars and galaxies in existence account for just about 5% of the mass-energy density of the universe. Amina Khan,, "After years of searching, scientists can finally account for all the normal matter in the universe," 20 June 2018 Ballantyne currently includes about 4 million square feet – would add a huge amount of new density on the site. Ely Portillo, charlotteobserver, "Here’s how Ballantyne tried to lure Amazon’s new headquarters to Charlotte," 24 Jan. 2018 Movement performed in water—due to its buoyancy, density and resistance—can help restore strength, mobility, balance and coordination, without the pain often... Laura Landro, WSJ, "The Health Benefits of Aquatic Therapy," 21 Apr. 2019 Foveros takes that into the third dimension, enabling even greater density and a reduced footprint. Peter Bright, Ars Technica, "Intel introduces Foveros: 3D die stacking for more than just memory," 12 Dec. 2018 The benefits of greater computational density and flexibility are obvious, but this modular approach also helps Intel skirt one of its biggest challenges: building full chips at 10nm scale. Vlad Savov, The Verge, "Intel unveils Foveros 3D chip stacking and new 10nm ‘chiplets’," 12 Dec. 2018 Opposition is based mainly on concern about possible storm water issues, the building height and density, and traffic congestion and safety, said Gerald Wolin, an Oak Brook Club resident and former Oak Brook Village Board member. Chuck Fieldman,, "Residents crowd Oak Brook meeting to oppose 22-story luxury condo development," 12 July 2018 Spiegel began to research the skeletal differences between cisgender men and women, finding marked differences in their bone shapes and densities. Serena Daniari, Allure, "The Complicated Process of Undergoing Facial-Feminization Surgery, and Why I Did It," 23 Mar. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'density.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of density

1598, in the meaning defined at sense 1

History and Etymology for density

see dense

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Statistics for density

Last Updated

13 May 2019

Look-up Popularity

Time Traveler for density

The first known use of density was in 1598

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More Definitions for density



English Language Learners Definition of density

: the quality of having parts that are close together
: the quality of being difficult to see through
: the quality of being difficult to understand


den·​si·​ty | \ ˈden-sə-tē How to pronounce density (audio) \
plural densities

Kids Definition of density

1 : the condition of having parts that are close together the jungle's density
2 : the amount of something in a specified volume or area high population density


den·​si·​ty | \ ˈden(t)-sət-ē, -stē How to pronounce density (audio) \
plural densities

Medical Definition of density

1 : the quantity per unit volume, unit area, or unit length: as
a : the mass of a substance per unit volume
b : the distribution of a quantity (as mass, electricity, or energy) per unit usually of space
c : the average number of individuals or units per space unit a population density of 500 per square mile
2a : the degree of opacity of a translucent medium

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Comments on density

What made you want to look up density? Please tell us where you read or heard it (including the quote, if possible).


a strong desire or propensity

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