The Collaborative International Dictionary of English v.0.48:

Hesitation \Hes`i*ta"tion\, n. [L. haesitatio: cf. F.
   h['e]sitation.]
   1. The act of hesitating; suspension of opinion or action;
      doubt; vacillation.
      [1913 Webster]

   2. A faltering in speech; stammering. --Swift.
      [1913 Webster]

WordNet (r) 3.0 (2006):

hesitation
    n 1: indecision in speech or action [syn: hesitation,
         vacillation, wavering]
    2: a certain degree of unwillingness; "a reluctance to commit
       himself"; "his hesitancy revealed his basic indisposition";
       "after some hesitation he agreed" [syn: reluctance,
       hesitancy, hesitation, disinclination, indisposition]
    3: the act of pausing uncertainly; "there was a hesitation in
       his speech" [syn: hesitation, waver, falter,
       faltering]

Moby Thesaurus II by Grady Ward, 1.0:

159 Moby Thesaurus words for "hesitation":
   Fabian policy, Micawberism, abeyance, averseness, backwardness,
   balbuties, bashfulness, boggle, boggling, break, caesura,
   calculation, canniness, capriciousness, care,
   careful consideration, carefulness, caution, cautiousness,
   cease-fire, chance, chanciness, changeableness, circumspection,
   compunction, courtesan, day off, delay, deliberate stages,
   deliberateness, deliberation, demimondaine, demimonde, demirep,
   demur, demurral, diffidence, dilatoriness, discretion, doubt, drop,
   dubiety, dysphemia, erraticism, erraticness, falter, faltering,
   fancy woman, fickleness, gingerliness, guardedness, hedge, hedging,
   heed, heedfulness, hesitance, hesitancy, hesitating, hetaera,
   hold-off, holiday, incalculability, incertitude, indecision,
   indecisiveness, indemonstrability, indeterminacy, indetermination,
   indeterminism, indisposition, interim, interlude, intermezzo,
   intermission, intermittence, interruption, interval, irresolution,
   judiciousness, kept, lapse, laxness, layoff, letup, luck, lull,
   mindfulness, mistrust, modesty, mugwump, objection, palilalia,
   pause, pawkiness, prior consultation, procrastination, protest,
   prudence, prudentialness, qualm, qualm of conscience, qualmishness,
   randomness, recess, recoil, regardfulness, reluctance, remission,
   remissness, respite, rest, safeness, safety first, scruple,
   scrupulosity, scrupulousness, shilly-shally, shilly-shallying,
   shrinking, shyness, slackness, slowness, slowness to act,
   solicitude, stall, stammer, stammering, stand-down, stay,
   stickling, stutter, stuttering, suspense, suspensefulness,
   suspension, temporization, tentativeness, thoroughness, to-and-fro,
   traulism, truce, unaccountability, uncertainness, uncertainty,
   uncertainty principle, uncommunicativeness, undecidedness,
   undeterminedness, unforeseeableness, unprecipitateness,
   unpredictability, unprovability, unsureness, unverifiability,
   vacation, vacillation, wavering, whimsicality, whore