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

jitters \jitters\ n.
   an uneasy state; nervousness; as, the prospect of being
   drafted gave him a bad case of the jitters.

   syn: nervousness, nerves, screaming meemies.
        wordnet 1.5

[2] : WordNet (r) 2.0

jitters
     n : extreme nervousness syn: heebie-jeebies, screaming
         meemies
see also:
heebie-jeebies screaming meemies 

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

81 moby thesaurus words for "jitters":
   agitation, all-overs, apprehension, apprehensiveness, bluster,
   bobbery, boil, boiling, brouhaha, bustle, churn, cold shivers,
   cold sweat, commotion, conturbation, discomposure, disorder,
   disquiet, disquietude, disturbance, dither, dithers, ebullition,
   embroilment, excitement, ferment, fermentation, fever,
   feverishness, fidgets, flap, flurry, fluster, flutteration, foment,
   fume, fuss, heebie-jeebies, hubbub, hurly-burly, inquietude,
   jimjams, jumpiness, jumps, maelstrom, malaise, moil, nerves,
   nerviness, nervosity, nervousness, perturbation, queasiness,
   quivers, restlessness, roil, rout, row, seethe, seething, shakes,
   shivers, skittishness, stir, sweat, swirl, to-do, trembles,
   trepidation, trepidity, tumult, tumultuation, turbidity,
   turbulence, turmoil, twitter, unease, uneasiness, unrest, upset,
   willies

Jitters >> J Words
Jitters, definition of term: Jitters
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