dense

UK: /ˈdɛns/ US: /dɛns/ ,(dens)

Inflections of 'dense' (adj):

denser

adj comparative

densest

adj superlative

WordReference Random House Learner's Dictionary of American English © 2025

dense /dɛns/   adj., dens•er, dens•est. 

1. having parts closely packed together;
   crowded:
   a dense forest.
2. stupid;
   slow-witted.
3. thick;
   intense;
   difficult to see through:
   a very dense fog.
4. difficult to understand:
   dense writing.

dense•ly, adv. 
dense•ness, n. [uncountable]

WordReference Random House Unabridged Dictionary of American English © 2025

dense  (dens), adj., dens•er, dens•est. 

1. having the component parts closely compacted together;
   crowded or compact:
   a dense forest; dense population.
2. stupid;
   slow-witted;
   dull.
3. intense;
   extreme:
   dense ignorance.
4. Photography 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 pertaining 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.

• Latin dēnsus thick; cognate with Greek dasýs
• 1590–1600

dense′ly, adv. 
dense′ness, n. 
Synonyms

• 1. congested, crammed, teeming; impenetrable.

Collins Concise English Dictionary © HarperCollins Publishers::

dense / dɛns/ adjective

1. thickly crowded or closely set: a dense crowd
2. thick; impenetrable
3. having a high density
4. stupid; dull; obtuse
5. (of a photographic negative) having many dark or exposed areas

Etymology: 15th Century: from Latin densus thick; related to Greek dasus thickly covered with hair or leaves