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

weariness \wea"riness\, n.
   the quality or state of being weary or tried; lassitude;
   exhaustion of strength; fatigue.
   1913 webster

         with weariness and wine oppressed.       --dryden.
   1913 webster

         a man would die, though he were neither valiant nor
         miserable, only upon a weariness to do the same thing
         so oft over and over.                    --bacon.
   1913 webster
   1913 webster

[2] : WordNet (r) 2.0

weariness
     n : temporary loss of strength and energy resulting from hard
         physical or mental work; "he was hospitalized for extreme
         fatigue"; "growing fatigue was apparent from the decline
         in the execution of their athletic skills"; "weariness
         overcame her after twelve hours and she fell asleep"
         syn: fatigue, tiredness
see also:
fatigue tiredness 

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

95 moby thesaurus words for "weariness":
   acedia, adynamia, anemia, apathy, atony, blah feeling,
   bloodlessness, boredness, boredom, brain fag, bromidic, cachexia,
   cachexy, cowardice, debilitation, debility, dispiritedness,
   drowsiness, dry, dryasdust, dull, dullness, dusty, enervation,
   enfeeblement, ennui, etiolation, exhaustion, eyestrain, faintness,
   fatigue, fed-upness, feebleness, flabbiness, flaccidity, goneness,
   heart strain, heaviness, hebetude, impotence, inanimation,
   indifference, insipid, jadedness, lackadaisicalness, languidness,
   languishment, languor, languorousness, lassitude, lenitude, lentor,
   lethargy, life-weariness, lifelessness, listlessness, melancholy,
   mental fatigue, mental strain, oscitancy, overstrain,
   overtiredness, passivity, phlegm, prostration, satedness,
   satiation, satiety, sleepiness, sloth, slothfulness, slowness,
   sluggishness, softness, somnolence, spleen, stance fatigue, strain,
   strengthlessness, stupefaction, stupor, supineness, taedium vitae,
   tedious, tiredness, torpidity, torpidness, torpitude, torpor,
   uninteresting, weakliness, weakness, weariful, wearifulness,
   world-weariness

Weariness >> W Words
Weariness, definition of term: Weariness
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