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

sluggish \slug"gish\, a.
   1. habitually idle and lazy; slothful; dull; inactive; as, a
      sluggish man.
      1913 webster

   2. slow; having little motion; as, a sluggish stream.
      1913 webster

   3. having no power to move one's self or itself; inert.
      1913 webster

            matter, being impotent, sluggish, and inactive, hath
            no power to stir or move itself.      --woodward.
      1913 webster

            and the sluggish land slumbers in utter neglect.
                                                  --longfellow.
      1913 webster

   4. characteristic of a sluggard; dull; stupid; tame; simple.
      r. "so sluggish a conceit." --milton.
      1913 webster

   syn: inert; idle; lazy; slothful; indolent; dronish; slow;
        dull; drowsy; inactive. see inert.
        1913 webster -- slug"gishly, adv. --
        slug"gishness, n.
        1913 webster
see also:
inert slug"gishly slug"gishness 

[2] : WordNet (r) 2.0

sluggishness
     n 1: a state of comatose torpor as found in sleeping sickness
          syn: lethargy, lassitude
     2: inactivity; showing an unusual lack of energy syn: languor,
         lethargy, phlegm
see also:
lethargy lassitude languor phlegm 

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

19 moby thesaurus words for "sluggishness":
   hebetude, idleness, indolence, laggardness, languidness, languor,
   lassitude, laze, laziness, lethargy, lifelessness, phlegm,
   pococurantism, shiftlessness, sloth, slothfulness, slouch,
   stagnation, torpor

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