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Synonyms

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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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.

Keep Reading on Vocabulary.com

Vocabulary lists containing dense

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Denser sponges held up better over time and released fewer microplastic fibers, while less dense versions broke down more quickly.

From Science Daily • Apr. 18, 2026

“We’re operating in dense cities where new supply is structurally limited,” she says, and with automation, she believes, Stuf can scale up quickly as demand increases.

From The Wall Street Journal • Apr. 15, 2026

The entire space is dripping in the dense Black L.A.-meets-Egyptology that has become Halsey’s signature.

From Los Angeles Times • Apr. 14, 2026

The forests are dense and the region's porous borders make it easy for the militants to set up bases and to move across countries without being detected by the security forces.

From BBC • Apr. 9, 2026

Most of the Ho Chi Minh Trail was covered with dense forest, making it hard to hit from the air.

From "Most Dangerous: Daniel Ellsberg and the Secret History of the Vietnam War" by Steve Sheinkin