The Collaborative International Dictionary of English v.0.48:

Falter \Fal"ter\, v. i. [imp. & p. p. Faltered; p. pr. & vb.
   n. Faltering.] [OE. falteren, faltren, prob. from fault.
   See Fault, v. & n.]
   1. To hesitate; to speak brokenly or weakly; to stammer; as,
      his tongue falters.
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            With faltering speech and visage incomposed.
                                                  --Milton.
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   2. To tremble; to totter; to be unsteady. "He found his legs
      falter." --Wiseman.
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   3. To hesitate in purpose or action.
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            Ere her native king
            Shall falter under foul rebellion's arms. --Shak.
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   4. To fail in distinctness or regularity of exercise; -- said
      of the mind or of thought.
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            Here indeed the power of disinct conception of space
            and distance falters.                 --I. Taylor.
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The Collaborative International Dictionary of English v.0.48:

Faltering \Fal"ter*ing\, a.
   Hesitating; trembling. "With faltering speech." --Milton. --
   n. Falter; halting; hesitation. -- Fal"ter*ing*ly, adv.
   [1913 Webster]

WordNet (r) 3.0 (2006):

faltering
    adj 1: unsteady in speech or action
    n 1: 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:

90 Moby Thesaurus words for "faltering":
   ambling, balbutient, bashful, boggling, cautious, circumspect,
   claudicant, crawling, creeping, creeping like snail, deliberate,
   demurring, diffident, easy, flagging, foot-dragging, gentle,
   gradual, halting, hesitant, hesitating, hobbled, hobbling, idle,
   indecisive, indolent, irresolute, jibbing, languid, languorous,
   lazy, leisurely, limping, lukewarm, lumbering, moderate, modest,
   poking, poky, qualmish, relaxed, reluctant, sauntering, scrupling,
   scrupulous, shilly-shallying, shrinking, shuffling, shy, slack,
   slothful, slow, slow as death, slow as molasses, slow as slow,
   slow-crawling, slow-foot, slow-going, slow-legged, slow-moving,
   slow-paced, slow-poky, slow-running, slow-sailing, slow-stepped,
   sluggish, snail-paced, snaillike, squeamish, staggering,
   stammering, sticking, stickling, straining, strolling, stumbling,
   stuttering, tentative, timid, toddling, tortoiselike, tottering,
   trudging, turtlelike, uncertain, unhurried, vacillatory, waddling,
   wavering, wobbly