The Collaborative International Dictionary of English v.0.48:

Restive \Rest"ive\ (r?st"?v), a. [OF. restif, F. r['e]tif, fr.
   L. restare to stay back, withstand, resist. See Rest
   remainder, and cf. Restiff.] .
   Unwilling to go on; obstinate in refusing to move forward;
   stubborn; drawing back.
   [1913 Webster]

         Restive or resty, drawing back, instead of going
         forward, as some horses do.              --E. Philips
                                                  (1658).
   [1913 Webster]

         The people remarked with awe and wonder that the beasts
         which were to drag him [Abraham Holmes] to the gallows
         became restive, and went back.           --Macaulay.
   [1913 Webster]

   2. Inactive; sluggish. [Obs.] --Sir T. Browne.
      [1913 Webster]

   3. Impatient under coercion, chastisement, or opposition;
      refractory.
      [1913 Webster]

   4. Uneasy; restless; averse to standing still; fidgeting
      about; -- applied especially to horses. --Trench.
      [1913 Webster] -- Rest"ive, adv. -- Rest"ive*ness, n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

restive
    adj 1: being in a tense state [syn: edgy, high-strung,
           highly strung, jittery, jumpy, nervy,
           overstrung, restive, uptight]
    2: impatient especially under restriction or delay; "the
       government has done nothing to ease restrictions and
       manufacturers are growing restive"

Moby Thesaurus II by Grady Ward, 1.0:

151 Moby Thesaurus words for "restive":
   antsy, antsy-pantsy, anxious, apathetic, backward, balking, balky,
   beefing, bellyaching, beyond control, bigoted, bitching, breachy,
   breathless, bulldogged, bulletheaded, bullheaded, case-hardened,
   chafing, complaining, complaintful, contumacious, crabbing, crabby,
   cranky, croaking, cross-grained, defiant, dilatory, disappointed,
   discontented, disgruntled, displeased, dissatisfied, dogged,
   dogmatic, eager, edgy, envious, excited, fanatic, faultfinding,
   fidgety, fluttery, fractious, fretful, fretting, froward, fussy,
   griping, grouchy, grousing, growling, grudging, grumbling,
   hardheaded, hasty, headstrong, hopped-up, impatient,
   impatient of control, impetuous, in a lather, in a stew,
   in a sweat, incorrigible, indifferent, indocile, indomitable,
   insuppressible, intolerant, intractable, irrepressible, laggard,
   loath, malcontent, malcontented, mulish, murmuring, muttering,
   nervy, obstinate, obstreperous, on edge, opinionated, ornery,
   out of hand, out of humor, overzealous, peevish, perfunctory,
   persevering, pertinacious, perverse, petulant, pigheaded,
   querulant, querulous, rebellious, recalcitrant, refractory,
   reluctant, renitent, resentful, resistant, resisting, restless,
   self-willed, set, shrewish, slow, slow to, squirming, squirmy,
   stiff-necked, strong-willed, strongheaded, stubborn, sulky, sullen,
   tenacious, tense, unaccepting, unaccommodating, unbiddable,
   uncontrollable, uncooperative, uneasy, unenthusiastic, unfulfilled,
   ungovernable, ungratified, unhappy, unmalleable, unmanageable,
   unmoldable, unpatient, unquiet, unregenerate, unrestful, unruly,
   unsatisfied, unsettled, unsubmissive, unzealous, uptight, wayward,
   whiny, wild, willful, wrongheaded