[1] : WordNet (r) 2.0

insomniac
     adj : experiencing or accompanied by sleeplessness; "insomniac old
           people"; "insomniac nights"; "lay sleepless all night";
           "twenty watchful, weary, tedious nights"- shakespeare
           syn: sleepless, watchful
     n : someone who cannot sleep syn: sleepless person
see also:
sleepless watchful sleepless person 

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

20 moby thesaurus words for "insomniac":
   alertness, all-night vigil, consciousness, insomnia, insomnious,
   insomnolence, insomnolency, lidless vigil, restless, restlessness,
   sentience, sleepless, sleeplessness, slumberless,
   tossing and turning, unsleeping, vigil, wake, wakeful,
   wakefulness

Insomniac >> I Words
Insomniac, definition of term: Insomniac
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