The Collaborative International Dictionary of English v.0.48:

Edgy \Edg"y\, a. [From Edge.]
   1. Easily irritated; sharp; as, an edgy temper.
      [1913 Webster]

   2. (Fine Arts) Having some of the forms, such as drapery or
      the like, too sharply defined. "An edgy style of
      sculpture." --Hazlitt.
      [1913 Webster]

WordNet (r) 3.0 (2006):

edgy
    adj 1: being in a tense state [syn: edgy, high-strung,
           highly strung, jittery, jumpy, nervy,
           overstrung, restive, uptight]

Moby Thesaurus II by Grady Ward, 1.0:

58 Moby Thesaurus words for "edgy":
   agitable, all nerves, antsy, antsy-pantsy, anxious, apprehensive,
   breathless, chafing, combustible, eager, emotional,
   emotionally unstable, eruptive, excitable, excited, explosive,
   fearful, fretful, fretting, frightened, hasty, high-mettled,
   high-spirited, high-strung, highly emotional, hopped-up, impatient,
   impetuous, in a lather, in a stew, in a sweat, inflammable,
   irascible, irritable, mettlesome, nerves on edge, nervous, nervy,
   on edge, overstrung, panicky, perturbable, prickly, restive,
   restless, sensitive, skittery, skittish, squirming, squirmy,
   startlish, touchy, uneasy, unpatient, unquiet, uptight, volatile,
   volcanic