if used as a figurative (of a text), then dense means it's hard to understand because of a complexity of ideas...

if dense is used as figurative (of a person), then dense means that it's difficult to explain anything to that person because they can't make sense of complex ideas (because their head is too "dense" or "thick" to get anything through)

It does not mean stupid although it is often used to describe people who are also stupid. For example, a lawyer who argues what the word "is" means could be described as dense. Stupid is lacking in intelligence whereas dense infers that a person's head is too thick to teach anything to him/her.

People who exhaust you by asking for further clarification on anything from policies and procedures by asking questions they wouldn't ask had they understood your previous answer to one of their previous questions are dense - their skulls are too thick to get anything through to their heads so they don't understand even the simplest lowest common denominator definitions!

A dense person is the opposite of an airhead, although about as useful.
If you had to read this definition several times to understand it - and you still don't really understand it, it is because you are dense.
by unicornmoans April 23, 2010
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- (adj.) relating to matter per unit squared science
- (adj.) someone who lacks common sense, or humiliates themself
- (n.) someone of ignorance; someone of disgrace
Water isn't very dense, with an approximate 1.00 g/mL.

Ryan is very dense. He makes a fool of herself daily!

... is a dense.
by urbandictionarytom March 8, 2015
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Whenever someone say's something retarded
Tim: How are you watching that song while reading that book?
Me: Obviously I'm listening to the song while reading the book.
Oh man it's getting really dense in here.
by LoOped October 3, 2011
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Dealer: Here you go man.
Pothead: Are you sure this is an eighth?
Dealer: Yea,it's really dense man.
Pothead: Well let me whip out my scale. (Places nugs on scale. Scale reads 2.7g.
Dealer: I'm sure it's dried a little.
Pothead: Yeah right. (Knocks dealer to the floor)
by Twibbix September 20, 2004
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adj. used to describe people who..would laugh at dumb shit, has slow brain processing, is always red,talks shit about strangers behind their backs, blonde.

Synonyms: blonde, paris hilton, britney

oh and probably has down syndrome also.
C Au.! milk comes from COWS not the supermakets!! stop being dense!
by Teee Heee July 11, 2008
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