Dictionary.com
Thesaurus.com
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.

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

Number of days with dense fog since Oct.

From The Wall Street Journal • Mar. 29, 2026

This is because the sunlight it reflects reaches us through a more dense part of the Earth's atmosphere which scatters blue and violet light, and means only the redder hues reach us.

From BBC • Mar. 29, 2026

Inside the stainless-steel pot, blue corn powder was amassing into tiny balls that grew into dense lumps.

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith