denser; densest
1
a
: marked by compactness or crowding together of parts
dense vegetation
dense traffic
b
chemistry : having a high mass (see mass entry 2 sense 1c) per unit volume (see volume entry 1 sense 2)
Carbon dioxide is a dense gas.
The cake was overly sweet and dense.
2
a
: slow to understand : stupid, thickheaded
was too dense to get the joke
b
: extreme
dense ignorance
3
mathematics : having between any two elements at least one element
The set of rational numbers is dense.
4
: demanding concentration to follow or comprehend
dense prose
5
: having high or relatively high opacity (see opacity sense 2)
a dense fog
a dense photographic negative
densely adverb
denseness noun
Choose the Right Synonym for dense

stupid, dull, dense, crass, dumb mean lacking in power to absorb ideas or impressions.

stupid implies a slow-witted or dazed state of mind that may be either congenital or temporary.

stupid students just keeping the seats warm
stupid with drink

dull suggests a slow or sluggish mind such as results from disease, depression, or shock.

monotonous work that leaves the mind dull

dense implies a thickheaded imperviousness to ideas.

too dense to take a hint

crass suggests a grossness of mind precluding discrimination or delicacy.

a crass, materialistic people

dumb applies to an exasperating obtuseness or lack of comprehension.

too dumb to figure out what's going on

Examples of dense in a Sentence

They cut a path through the dense jungle. a dense tangle of wires a dense cluster of stars That part of the city has a dense population of immigrants. A dense mass of spectators filled the courtroom. In the movie, she plays his kind but somewhat dense aunt.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Today’s top stories San Diego small plane crash A private jet flying in dense fog crashed into a San Diego neighborhood early Thursday morning, leaving a huge debris field. Hailey Branson-Potts, Los Angeles Times, 23 May 2025 However, researchers observed that after being dispersed by the radiation, the clouds were not dense or large enough to create new stars. Kameryn Griesser, CNN Money, 23 May 2025 The cause of the crash also remains unclear, but officials said Friday that the weather alert system and runway lights weren’t working at the airport when the jet attempted to land amid dense fog around 3:45 a.m. Brian Niemietz, New York Daily News, 23 May 2025 These included underwater currents and katabatic winds—the wind generated as a mountain’s dense, cool, high-altitude air flows into a lower elevation. Andrew Paul, Popular Science, 22 May 2025 See All Example Sentences for dense

Word History

Etymology

Latin densus; akin to Greek dasys thick with hair or leaves

First Known Use

15th century, in the meaning defined at sense 1a

Time Traveler
The first known use of dense was in the 15th century

Browse Nearby Words

Cite this Entry

“Dense.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dense. Accessed 29 May. 2025.

Kids Definition

dense

adjective
denser; densest
1
a
: marked by closeness or crowding together of parts
a dense forest
b
: having a high mass per unit volume
lead is a very dense metal
2
: slow to understand : stupid sense 1a
3
: thick entry 1 sense 4
dense fog
4
: having between any two mathematical elements at least one element
the set of rational numbers is dense
densely adverb
denseness noun

More from Merriam-Webster on dense

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