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 of dense

• 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

The texture is dense, oily, and mouth-coating, with substantial weight and a firm grip from the first sip. —Joseph V Micallef, Forbes.com, 24 May 2026

Motorists may encounter patches of dense fog within these areas that further reduces visibility to near 0 at times. —Nc Weather Bot, Charlotte Observer, 24 May 2026

Travelers often pack food that looks suspicious on X-ray, like powders and dense snacks, says the TSA spokesperson. —Jillian Dara, Travel + Leisure, 24 May 2026

This stretch of the Beltline features wildflowers, dense tree canopies and residential areas. —Olivia Wakim, AJC.com, 24 May 2026

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