dense

adjective

ˈden(t)s 

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

ˈden(t)-snəs 

noun

Synonyms

• crowded
• thick
• packed
• tight
• compact

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

Instead, Hoyle claimed that the vast majority of atoms came from stars that died, and not from this early, hot, dense state. —Ethan Siegel, Big Think, 11 Sep. 2025

Open star clusters are loose and irregular groups of stars that are often younger and contain fewer stars when compared to denser globular clusters. —Harry Bennett, Space.com, 11 Sep. 2025

Some subdomains showed higher fluorescence intensity and spectral shifts, marking denser and chemically altered environments. —Aamir Khollam, Interesting Engineering, 11 Sep. 2025

In Tanzania, visitors can see wild chimpanzees, huge lion prides, the incredible mass birthing of wildebeest in late February and early March, and dense concentrations of elephants in the dry season from June to October. —Kent Redding, Travel + Leisure, 10 Sep. 2025

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

Rhymes for dense

• cense
• fence
• hence
• lense
• mense
• sense
• tense
• thence
• whence
• antisense
• commonsense
• effulgence

Kids Definition

dense

adjective

ˈden(t)s 

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