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 connected network of poles allowed the blaze to move between buildings, an event described as rare in Hong Kong’s dense housing estates. —Sujita Sinha, Interesting Engineering, 27 Nov. 2025

This cashmere tree is dense and full, with fluffy branches that reinforce its natural look. —Stephanie Osmanski, Better Homes & Gardens, 27 Nov. 2025

In situations of near-zero visibility due to dense fog, activate your hazard lights and seek a secure location, such as a nearby business’s parking lot, to pull over and come to a stop. —Bay Area Weather Report, Mercury News, 27 Nov. 2025

Add Canned Sardines to Snacks Canned sardines are one of the most nutrient-dense, omega-3-rich foods available. —Morgan Pearson, Verywell Health, 27 Nov. 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