WordNet (r) 3.0 (2006):

giveaway
    n 1: a gift of public land or resources for the private gain of
         a limited group
    2: an unintentional disclosure
    3: a television or radio program in which contestants compete
       for awards [syn: game show, giveaway]

Moby Thesaurus II by Grady Ward, 1.0:

120 Moby Thesaurus words for "giveaway":
   Grand Guignol, Passion play, Tom show, antimasque,
   audience success, babbling, ballet, best, betrayal, blabbering,
   blabbing, bomb, bottom, broadcast drama, burlesque show, charade,
   cliff hanger, closet drama, comedy drama, communication leak,
   critical success, cut, daytime serial, dead giveaway, dialogue,
   divulgation, divulgement, divulgence, divulging, documentary drama,
   drama, dramalogue, dramatic play, dramatic series, duodrama,
   duologue, epic theater, evulgation, experimental theater,
   extravaganza, failure, flop, gasser, half-price, happening, hit,
   hit show, improvisational drama, indiscretion, leak,
   legitimate drama, letting out, lowest, marked down, masque,
   melodrama, minstrel show, miracle, miracle play, monodrama,
   monologue, morality, morality play, music drama, musical revue,
   mystery, mystery play, obvious clue, opera, pageant, panel show,
   pantomime, pastoral, pastoral drama, piece, play, playlet,
   problem play, psychodrama, quiz show, radio drama, reduced, review,
   revue, rock-bottom, sacrificial, sensational play, serial, show,
   sitcom, situation comedy, sketch, skit, slashed, soap, soap opera,
   sociodrama, spectacle, stage play, stage show, straight drama,
   success, suspense drama, tableau, tableau vivant, talk show,
   teleplay, television drama, television play, telltale,
   telltale sign, theater of cruelty, total theater,
   unwitting disclosure, variety show, vaudeville, vaudeville show,
   vehicle, word-of-mouth success, work