WordNet (r) 3.0 (2006):

what for
    n 1: a strong reprimand

Moby Thesaurus II by Grady Ward, 1.0:

67 Moby Thesaurus words for "what for":
   ass-reaming, bawling-out, castigation, chastening, chastisement,
   chewing, condign punishment, correction, cussing-out, deserts,
   disciplinary measures, discipline, dressing, dressing-down, excuse,
   explanation, ferule, for which, for why, from what cause,
   going-over, how come, infliction, jacking-up, judgment,
   judicial punishment, nemesis, on what account, pains,
   pains and punishments, pay, payment, penal retribution, penalty,
   penology, pourquoi, pretense, pretext, punishment, punition,
   raking-down, rational ground, rationale, reaming, reaming-out,
   reason, reason for, reason why, retribution, retributive justice,
   roasting, scourge, setdown, speaking-to, stated cause, talking-to,
   the big idea, the idea, the whatfor, the wherefore, the why,
   underlying reason, well-deserved punishment, wherefore, why,
   whyever, whyfor