Tremor

tremor
    n 1: an involuntary vibration (as if from illness or fear) [syn:
         {tremor}, {shudder}]
    2: a small earthquake [syn: {tremor}, {earth tremor},
       {microseism}]
    3: shaking or trembling (usually resulting from weakness or
       stress or disease)
    v 1: shake with seismic vibrations; "The earth was quaking"
         [syn: {tremor}, {quake}]
    

Tremor \Tre"mor\, n. [L., from tremere to tremble. See
   {Tremble}, v.]
   A trembling; a shivering or shaking; a quivering or vibratory
   motion; as, the tremor of a person who is weak, infirm, or
   old.
   [1913 Webster]

         He fell into an universal tremor of all his joints.
                                                  --Harvey.
   [1913 Webster] Tremulant
    

117 Moby Thesaurus words for "tremor":
      Bebung, aphonia, artificial voice, bang, bob, bobble, boot, bounce,
      broken speech, broken tones, broken voice, bump, charge,
      childish treble, choked voice, cracked voice, croak, crow, didder,
      disquiet, disquietude, dither, dithers, dysarthria, dyslalia,
      dyslogia, dysphasia, dysphonia, dysphrasia, falsetto, falter,
      fidgetiness, fidgets, flush, flutter, grimace, harshness,
      hawking voice, heaving, hiss, hoarseness, idioglossia, idiolalia,
      impairment of speech, inquietude, jar, jerk, jig, jigget, jiggle,
      jog, joggle, jollies, jolt, jostle, kick, lift, lisp, lisping,
      loss of voice, muzzy speech, nasal tone, nasalization, palpitation,
      panting, pitapat, pitter-patter, quake, quaker, quaking, quaver,
      quavering, quiver, quivering, restlessness, rictus, rush,
      rush of emotion, sensation, shake, shakes, shaking, shiver,
      shivers, shock, shudder, sibilation, speech defect,
      speech impediment, surge of emotion, temblor, thrill, throb,
      throbbing, tic, tingle, tingling, titillation, tremble, trembling,
      tremolando, tremolant, tremolo, tremor of excitement, trepidation,
      trepidity, trill, trillet, trilleto, trillo, twang, twitch,
      twitter, unrest, vibrate, vibrato, wobble