dense

American  

[dens] / dɛns /

adjective

denser, densest

1. having the component parts closely compacted together; crowded or compact.

   a dense forest;

   dense population.

   Synonyms:

   impenetrable, teeming

2. stupid; slow-witted; dull.

3. intense; extreme.

   dense ignorance.

4. relatively opaque; transmitting little light, as a photographic negative, optical glass, or color.

5. difficult to understand or follow because of being closely packed with ideas or complexities of style.

   a dense philosophical essay.

6. Mathematics. of or relating to a subset of a topological space in which every neighborhood of every point in the space contains at least one point of the subset.

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dense British  

/ dɛns /

adjective

1. thickly crowded or closely set

   a dense crowd

2. thick; impenetrable

   a dense fog

3. physics having a high density

4. stupid; dull; obtuse

5. (of a photographic negative) having many dark or exposed areas

6. (of an optical glass, colour, etc) transmitting little or no light

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Other Word Forms

• densely
  adverb
• denseness
  noun
• nondenseness
  noun
• superdense
  adjective
• ultradense
  adjective

Etymology

Origin of dense

First recorded in 1590–1600; from Latin dēnsus “thick”; cognate with Greek dasýs

Explanation

When woods are dense, the trees grow close together. When fog is dense, you can't see through it. And if someone calls you dense, they think nothing can get into your thick skull. Dense comes from the Latin densus which means thick and cloudy. In general, the word means packed tight and gives the sense that something is difficult to get through. Text can be dense in two different ways: when the words are packed closely together on the page, and when the text is filled with big words and complicated thoughts. Either way, reading dense text is just no fun.

Example Sentences

Yamazaki explained Tohoku has a dense bear population as "the number has been growing for about 20 years".

From Barron's • May 8, 2026

In this scenario, black holes formed from dying stars collide with each other, then merge again in dense stellar environments where stars are packed up to a million times more tightly than around our Sun.

From Science Daily • May 8, 2026

The 15-mile corridor from downtown to the sea runs through dense pockets of Koreatown and iconic stretches of L.A. from the Miracle Mile to Beverly Hills.

From Los Angeles Times • May 7, 2026

What comes out is dense, fudgy and — crucially — not bean-y.

From Salon • May 5, 2026

“It’s a number,” she said, looking at me as though I was dense.

From "The City Beautiful" by Aden Polydoros

Related Words

• heavy
• impenetrable
• opaque
• solid