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

sullen \sul"len\, a. oe. solein, solain, lonely, sullen;
   through old french fr. assumed ll. solanus solitary, fr. l.
   solus alone. see sole, a.
   1. lonely; solitary; desolate. obs. --wyclif job iii. 14.
      1913 webster

   2. gloomy; dismal; foreboding. --milton.
      1913 webster

            solemn hymns so sullen dirges change. --shak.
      1913 webster

   3. mischievous; malignant; unpropitious.
      1913 webster

            such sullen planets at my birth did shine. --dryden.
      1913 webster

   4. gloomily angry and silent; cross; sour; affected with ill
      humor; morose.
      1913 webster

            and sullen i forsook the imperfect feast. --prior.
      1913 webster

   5. obstinate; intractable.
      1913 webster

            things are as sullen as we are.       --tillotson.
      1913 webster

   6. heavy; dull; sluggish. "the larger stream was placid, and
      even sullen, in its course." --sir w. scott.
      1913 webster

   syn: sulky; sour; cross; ill-natured; morose; peevish;
        fretful; ill-humored; petulant; gloomy; malign;
        intractable.

   usage: sullen, sulky. both sullen and sulky show
          themselves in the demeanor. sullenness seems to be an
          habitual sulkiness, and sulkiness a temporary
          sullenness. the former may be an innate disposition;
          the latter, a disposition occasioned by recent injury.
          thus we are in a sullen mood, and in a sulky fit.
          1913 webster

                no cheerful breeze this sullen region knows;
                the dreaded east is all the wind that blows.
                                                  --pope.
          1913 webster -- sul"lenly, adv. --
          sul"lenness, n.
          1913 webster
see also:
sole sullen sulky sul"lenly sul"lenness 

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

sullen \sul"len\, n.
   1. one who is solitary, or lives alone; a hermit. obs.
      --piers plowman.
      1913 webster

   2. pl. sullen feelings or manners; sulks; moroseness; as, to
      have the sullens. obs. --shak.
      1913 webster

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

sullen \sul"len\, v. t.
   to make sullen or sluggish. obs.
   1913 webster

         sullens the whole body with . . . laziness. --feltham.
   1913 webster

[4] : WordNet (r) 2.0

sullen
     adj 1: showing a brooding ill humor; "a dark scowl"; "the
            proverbially dour new england puritan"; "a glum,
            hopeless shrug"; "he sat in moody silence"; "a morose
            and unsociable manner"; "a saturnine, almost
            misanthropic young genius"- bruce bliven; "a sour
            temper"; "a sullen crowd" syn: dark, dour, glowering,
             glum, moody, morose, saturnine, sour
     2: darkened by clouds; "a heavy sky" syn: heavy, lowering,
         threatening
see also:
dark dour glowering glum moody morose 
saturnine sour heavy lowering threatening 

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

154 moby thesaurus words for "sullen":
   antisocial, at odds, autistic, averse, bad-tempered, balking,
   balky, bashful, beetle-browed, bigoted, black, black-browed,
   brooding, broody, bulldogged, bulletheaded, bullheaded,
   cantankerous, case-hardened, chapfallen, choleric, churlish, close,
   contrary, crabbed, crabby, cranky, crestfallen, cross,
   cross-grained, crotchety, crusty, cursory, cynical, dark, dejected,
   depressed, depressing, differing, difficult, disagreeing,
   disinclined, dismal, disobedient, dissociable, dogged, dogmatic,
   dour, dreary, dumpish, dyspeptic, fanatic, forced, fractious,
   fretful, froward, frowning, funereal, gloomy, glowering, glum,
   grim, grum, grumpy, hardheaded, headstrong, hostile, ill-humored,
   ill-natured, ill-tempered, incompatible, indisposed, indocile,
   insociable, intolerant, involuntary, irascible, long-faced,
   lowering, lugubrious, malevolent, malicious, malign, mean,
   melancholy, moodish, moody, mopey, moping, mopish, morose, mulish,
   mumpish, mutinous, nongregarious, obstinate, opinionated, opposed,
   ornery, out of humor, out of sorts, overzealous, peevish,
   perfunctory, persevering, pertinacious, perverse, pessimistic,
   petulant, pigheaded, pouting, recalcitrant, refractory, resistant,
   restive, runty, saturnine, scowling, self-contained,
   self-sufficient, self-willed, set, snug, socially incompatible,
   sour, splenetic, stiff-necked, strong-willed, strongheaded,
   stubborn, stuffy, sulking, sulky, surly, temperamental, tenacious,
   tenebrose, tenebrous, ugly, unclubbable, uncommunicative,
   uncompanionable, uncongenial, unconsenting, uncooperative,
   unfriendly, ungenial, unregenerate, unsociable, unsocial,
   unwilling, wayward, willful, wrongheaded

Sullen >> S Words
Sullen, definition of term: Sullen
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