The Collaborative International Dictionary of English v.0.48:

Spoil \Spoil\ (spoil), v. t. [imp. & p. p. Spoiled (spoild) or
   Spoilt (spoilt); p. pr. & vb. n. Spoiling.] [F. spolier,
   OF. espoillier, fr. L. spoliare, fr. spolium spoil. Cf.
   Despoil, Spoliation.]
   1. To plunder; to strip by violence; to pillage; to rob; --
      with of before the name of the thing taken; as, to spoil
      one of his goods or possessions. "Ye shall spoil the
      Egyptians." --Ex. iii. 22.
      [1913 Webster]

            My sons their old, unhappy sire despise,
            Spoiled of his kingdom, and deprived of eyes.
                                                  --Pope.
      [1913 Webster]

   2. To seize by violence; to take by force; to plunder.
      [1913 Webster]

            No man can enter into a strong man's house, and
            spoil his goods, except he will first bind the
            strong man.                           --Mark iii.
                                                  27.
      [1913 Webster]

   3. To cause to decay and perish; to corrupt; to vitiate; to
      mar.
      [1913 Webster]

            Spiritual pride spoils many graces.   --Jer. Taylor.
      [1913 Webster]

   4. To render useless by injury; to injure fatally; to ruin;
      to destroy; as, to spoil paper; to have the crops spoiled
      by insects; to spoil the eyes by reading.
      [1913 Webster]

WordNet (r) 3.0 (2006):

spoiled
    adj 1: having the character or disposition harmed by pampering
           or oversolicitous attention; "a spoiled child" [syn:
           spoiled, spoilt]
    2: (of foodstuffs) not in an edible or usable condition; "bad
       meat"; "a refrigerator full of spoilt food" [syn: bad,
       spoiled, spoilt]

Moby Thesaurus II by Grady Ward, 1.0:

130 Moby Thesaurus words for "spoiled":
   ausgespielt, bad, bankrupt, barfy, beautiless, blasted, blemished,
   blighted, blotted, botched, brackish, broken, bungled, butchered,
   cacophonic, cacophonous, cankered, carious, cloying, coddled,
   corrupt, decayed, decomposed, defaced, desolated, destroyed,
   devastated, disfigured, done for, done in, down-and-out,
   dysphemistic, dysphemized, fallen, festering, fetid, finished,
   flawed, foul, fulsome, fumbled, gangrened, gangrenous, gone bad,
   gone to pot, high, homely, icky, ill-advised, ill-considered,
   ill-contrived, ill-devised, ill-done, ill-executed, ill-managed,
   impaired, impolitic, in ruins, indulged, inelegant, irremediable,
   kaput, maggoty, marred, mawkish, misconducted, misdirected,
   misguided, mismanaged, mortified, muffed, murdered, nasty,
   nauseant, nauseating, nauseous, necrosed, necrotic, negligent,
   noisome, noxious, off, offensive, overripe, overthrown, pampered,
   peccant, plain, poisonous, putrefied, putrescent, putrid, rancid,
   rank, ravaged, rebarbative, rotten, rotting, ruined, ruinous,
   short on looks, sickening, sphacelated, spoiled rotten, spoilt,
   stinking, suppurating, suppurative, tainted, uglified, ugly,
   ugly as hell, ugly as sin, ulcerated, unaesthetic, unattractive,
   unbeautiful, uncomely, undone, unhandsome, unlovely, unpleasing,
   unpretty, unsightly, vile, vomity, wasted, weevily, wrecked,
   yucky