WordNet (r) 3.0 (2006):

peter out
    v 1: end weakly; "The music just petered out--there was no
         proper ending" [syn: taper off, peter out, fizzle
         out, fizzle]
    2: use up all one's strength and energy and stop working; "At
       the end of the march, I pooped out" [syn: poop out, peter
       out, run down, run out, conk out]

Moby Thesaurus II by Grady Ward, 1.0:

108 Moby Thesaurus words for "peter out":
   abate, bate, be annihilated, be consumed, be destroyed,
   be disappointing, be no more, be unproductive, be used up,
   be wiped out, blow, break, break down, burn out, cave in,
   cease to be, cease to exist, collapse, come apart, come short,
   come to naught, come to nothing, come unstuck, conk out, crack up,
   crumble, decline, die, die away, die out, diminish, disappear,
   disintegrate, dissolve, droop, drop, dry up, dwindle, evaporate,
   expire, fade, fade away, fade out, fail, faint, fall down,
   fall flat, fall short, fall through, fatigue, fizzle, fizzle out,
   flag, flee, fly, gasp, get bogged down, get hung up, get mired,
   get tired, give out, give way, go, go downhill, go soft,
   go to pieces, go wrong, grow weary, hang fire, hit the skids, jade,
   languish, leave no trace, lessen, lie fallow, melt away,
   not hack it, not make it, pant, pass, pass away, peg out, perish,
   pine, play out, poop out, puff, puff and blow, rebate, recede,
   run down, run dry, run out, sink, succumb, taper off, tire,
   turn sour, vanish, wane, waste, weaken, wear away, wear thin,
   weary, wheeze, wilt, yield