WordNet (r) 3.0 (2006):

vibrato
    n 1: (music) a pulsating effect in an instrumental or vocal tone
         produced by slight and rapid variations in pitch

Moby Thesaurus II by Grady Ward, 1.0:

76 Moby Thesaurus words for "vibrato":
   Bebung, English horn, bassoon, block flute, bombard, bourdon,
   cello, claribel, clarinet, clarion, concert flute, cornet,
   cornopean, cromorna, cymbel, diapason, dulciana, falter,
   flute stop, flutter, foundation stop, fourniture, gamba, gedeckt,
   gemshorn, harmonic flute, hybrid stop, koppel flute, larigot,
   melodia, mixture, mutation stop, nazard, oboe, octave, organ stop,
   piccolo, plein jeu, posaune, principal, quaver, quint, quintaten,
   quiver, rank, ranket, reed stop, register, rohr flute,
   sesquialtera, shake, shawm, spitz flute, stop, stopped diapason,
   stopped flute, string diapason, string stop, tierce, tremble,
   tremolando, tremolant, tremolo, tremor, trill, trillet, trilleto,
   trillo, trombone, trumpet, twelfth, unda maris, viola,
   voix celeste, vox angelica, vox humana