WordNet (r) 3.0 (2006):

unneeded
    adj 1: not necessary [syn: unnecessary, unneeded] [ant:
           necessary]

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "unneeded":
   de trop, dispensable, excess, expendable, expletive, gratuitous,
   in excess, needless, nonessential, pleonastic, prolix, redundant,
   spare, supererogatory, superfluous, tautologic, tautologous,
   to spare, uncalled-for, unessential, unnecessary, unrequired,
   verbose