den·si·ty | \ˈden(t)-sə-tē \
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

At a December 2015 meeting, the commission voted to cap the number of apartments at 142 units after some members said the proposal had too much density. Tom Daykin, Milwaukee Journal Sentinel, "After long debate, Germantown's Saxony Village is opening apartments aimed at millennials," 6 July 2018 Both TenCent, which owns WeChat, and Ant Financial, the Alibaba financial services arm that oversees AliPay, are aggressively trying to penetrate cities and regions that have a high density of Chinese travelers, Peterson says. Janelle Nanos,, "Businesses court Chinese tourists with WeChat, AliPay," 29 June 2018 The Eastside city’s downtown has a population density of about 18,000 people per square mile — similar to Seattle’s South Lake Union. Morning Brief, The Seattle Times, "A cool-down is coming, along with summer solstice | Wednesday Morning Brief, June 20," 20 June 2018 Atmospheric scientists don’t yet have the density of data nor the computer models to make huge improvements in this area. Brian Resnick, Vox, "What we’ve learned about hurricanes since last year’s devastating season.," 31 May 2018 Every guy has different hair density, texture, direction, and oil production. Adam Hurly, GQ, "The GQ Grooming Guide for College Graduates," 17 May 2018 If the State of Georgia had the population density of Haiti, its population would equal that of California and New York combined. Dana Snitzky, Longreads, "Is This the Most Crowded Island in the World? (And Why That Question Matters)," 20 Feb. 2018 In the memo, Coren said the project furthers several goals of the business district by investing in a vacant lot, adding commercial or office space and increasing residential density to support and attract other development. Karen Berkowitz,, "Once the site of proposed music venue, Bertucci's restaurant in Highwood now eyed for apartments," 25 June 2018 The planning commission found the apartment project will increase density in the area, which is consistent with Plan Cincinnati. Sharon Coolidge,, "What's next for land north of Cincinnati City Hall: Apartments or public radio?," 18 June 2018

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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Learn More about density

Phrases Related to density

population density

Statistics for density

Last Updated

14 Oct 2018

Look-up Popularity

Time Traveler for density

The first known use of density was in 1598

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More Definitions for density


den·si·ty | \ˈden-sə-tē \
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 \
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

b : absorbance

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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).


exaggeratedly or childishly emotional

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