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

sleepless \sleep"less\, a.
   1. having no sleep; wakeful.
      1913 webster

   2. having no rest; perpetually agitated. "biscay's sleepless
      bay." --byron.
      1913 webster -- sleep"lessly, adv. --
      sleep"lessness, n.
      1913 webster
see also:
sleep"lessly sleep"lessness 

[2] : WordNet (r) 2.0

sleeplessness
     n : a temporary state in which you are unable or unwilling to
         sleep syn: wakefulness ant: sleepiness
see also:
wakefulness sleepiness 

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

29 moby thesaurus words for "sleeplessness":
   acuity, acuteness, agility, alertness, all-night vigil, attention,
   attentiveness, brightness, consciousness, insomnia, insomniac,
   insomnolence, insomnolency, keenness, lidless vigil, nimbleness,
   promptitude, promptness, punctuality, quickness, readiness,
   restlessness, sentience, sharpness, smartness, tossing and turning,
   vigil, wake, wakefulness

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