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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

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.

Before long, she developed her own style, dense with symbols, drawing on what Ms. Ramírez calls her many “selfs.”

From The Wall Street Journal • Apr. 1, 2026

Giant anteaters have black and white diagonal stripes, dense shaggy hair and super-sized snouts.

From BBC • Apr. 1, 2026

Most armed insurgents were limited to central Chhattisgarh state's Bastar region, a vast mineral-rich sprawl of dense forests and hills, roughly the size of The Netherlands.

From Barron's • Mar. 30, 2026

Since large galaxies typically form in dense clusters, this raised questions.

From Science Daily • Mar. 30, 2026

He slipped Remember Me back in place and moved to another shelf, where he found a nice-looking, thick, dense book called Our Angry Earth, by Isaac Asimov and Frederik Pohl.

From "The First State of Being" by Erin Entrada Kelly