[1] : The Collaborative International Dictionary of English v.0.48

dense \dense\, a. l. densus; akin to gr. ? thick with hair or
   leaves: cf. f. dense.
   1. having the constituent parts massed or crowded together;
      close; compact; thick; containing much matter in a small
      space; heavy; opaque; as, a dense crowd; a dense forest; a
      dense fog.
      1913 webster

            all sorts of bodies, firm and fluid, dense and rare.
                                                  --ray.
      1913 webster

            to replace the cloudy barrier dense.  --cowper.
      1913 webster

   2. stupid; gross; crass; as, dense ignorance.
      1913 webster

[2] : WordNet (r) 2.0

dense
     adj 1: permitting little if any light to pass through because of
            denseness of matter; "dense smoke"; "heavy fog";
            "impenetrable gloom" syn: heavy, impenetrable
     2: closely crowded together; "a compact shopping center"; "a
        dense population"; "thick crowds" syn: compact, thick
     3: hard to pass through because of dense growth; "dense
        vegetation"; "thick woods" syn: thick
     4: having high relative density or specific gravity; "dense as
        lead"
     5: slow to learn or understand; lacking intellectual acuity;
        "so dense he never understands anything i say to him";
        "never met anyone quite so dim"; "although dull at
        classical learning, at mathematics he was uncommonly
        quick"- thackeray; "dumb officials make some really dumb
        decisions"; "he was either normally stupid or being
        deliberately obtuse"; "worked with the slow students"
        syn: dim, dull, dumb, obtuse, slow
see also:
heavy impenetrable compact thick dim dull 
dumb obtuse slow 

[3] : Moby Thesaurus II by Grady Ward, 1.0

161 moby thesaurus words for "dense":
   boeotian, adamantine, asinine, beef-brained, beef-witted,
   blockheaded, blockish, bony, bovine, bristling, broad-bodied,
   bulky, bullnecked, cement, cemental, chumpish, cloddish, close,
   close-knit, close-textured, close-woven, coarse, compact,
   compacted, compressed, concentrated, concrete, condensed,
   congested, consolidated, corneous, corpulent, cowish, crammed,
   crammed full, crass, crawling, crowded, diamondlike, dim,
   dim-witted, doltish, dull, dullard, dumb, duncical, duncish,
   durable, dure, enduring, exuberant, fat, fatheaded, firm,
   flintlike, flinty, flourishing, foolish, full, full-bodied, gluey,
   granitelike, granitic, gross, hard, hard as nails, hardhearted,
   heaped, heavy, heavyset, horny, impassable, impassive,
   impenetrable, impermeable, ineducable, iron-hard, ironlike,
   jam-packed, jammed, jungled, jungly, klutzy, lapideous, lasting,
   lethargic, lithoid, lithoidal, lumpish, lush, luxuriant, marble,
   marblelike, massed, massive, nonporous, numskulled, oafish,
   obdurate, obtuse, opaque, osseous, overgrown, overrun, packed,
   phlegmatic, piled, populous, rank, resistant, resistive, riotous,
   rocklike, rocky, rugged, serried, slow, slow-witted, sluggish,
   solid, sottish, sound, stable, steady, steellike, steely, stolid,
   stonelike, stony, stout, strong, stupid, sturdy, substantial,
   swarming, teeming, thick, thick-bodied, thick-growing,
   thick-witted, thickheaded, thickset, three-dimensional, tight,
   torpid, tough, unteachable, unweeded, unyielding, viscid, viscose,
   viscous, weed-choked, weed-ridden, weedy, well-built,
   well-constructed, well-founded, well-grounded, well-made,
   wrongheaded

Dense >> D Words
Dense, definition of term: Dense
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