The Collaborative International Dictionary of English v.0.48:

celesta \celesta\ n. (Mus.)
   a musical instrument consisting of graduated steel plates
   that are struck by hammers activated by a keyboard.
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

celesta
    n 1: a musical instrument consisting of graduated steel plates
         that are struck by hammers activated by a keyboard

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "celesta":
   battery, bells, bones, castanets, chime, chimes, clappers,
   crash cymbal, cymbals, finger cymbals, gamelan, glockenspiel, gong,
   handbells, idiophone, lyra, maraca, marimba, metallophone,
   orchestral bells, percussion, percussion instrument, percussions,
   percussive, rattle, rattlebones, sizzler, snappers, tam-tam,
   tintinnabula, tonitruone, triangle, tubular bells, vibes,
   vibraphone, xylophone