The Collaborative International Dictionary of English v.0.48:

Scath \Scath\ (sk[a^]th; 277), n. [Icel. ska[eth]i; akin to Dan.
   skade, Sw. skada, AS. scea[eth]a, sca[eth]a, foe, injurer,
   OS. ska[eth]o, D. schade, harm, injury, OHG. scade, G.
   schade, schaden; cf. Gr. 'askhqh`s unharmed. Cf. Scathe,
   v.]
   Harm; damage; injury; hurt; waste; misfortune. [Written also
   scathe.]
   [1913 Webster]

         But she was somedeal deaf, and that was skathe.
                                                  --Chaucer.
   [1913 Webster]

         Great mercy, sure, for to enlarge a thrall,
         Whose freedom shall thee turn to greatest scath.
                                                  --Spenser.
   [1913 Webster]

         Wherein Rome hath done you any scath,
         Let him make treble satisfaction.        --Shak.
   [1913 Webster] Scathe

The Collaborative International Dictionary of English v.0.48:

Scathe \Scathe\ (sk[=a][th]; 277), Scath \Scath\ (sk[a^]th;
   277), v. t. [imp. & p. p. Scathed (sk[=a][th]d or
   sk[a^]tht); p. pr. & vb. n. Scathing (sk[=a][th]"[i^]ng or
   sk[a^]th"-).] [Icel. ska[eth]a; akin to AS. scea[eth]an,
   sce[eth][eth]an, Dan. skade, Sw. skada, D. & G. schaden, OHG.
   scad[=o]n, Goth. ska[thorn]jan.]
   To do harm to; to injure; to damage; to waste; to destroy.
   [1913 Webster]

         As when heaven's fire
         Hath scathed the forest oaks or mountain pines.
                                                  --Milton.
   [1913 Webster]

         Strokes of calamity that scathe and scorch the soul.
                                                  --W. Irving.
   [1913 Webster]

WordNet (r) 3.0 (2006):

scathe
    n 1: the act of damaging something or someone [syn: damage,
         harm, hurt, scathe]

Moby Thesaurus II by Grady Ward, 1.0:

100 Moby Thesaurus words for "scathe":
   abuse, afflict, aggrieve, assail, attack, bankruptcy, befoul,
   bewitch, blight, blister, breakage, breakdown, castigate, collapse,
   condemn, corrupt, crack-up, crippling, crucify, curse, damage,
   defile, deprave, despoil, destroy, destruction, detriment,
   dilapidation, disablement, disadvantage, disrepair, disserve,
   distress, do a mischief, do evil, do ill, do wrong, do wrong by,
   doom, encroachment, envenom, excoriate, flay, fustigate,
   get into trouble, give the business, harass, harm, hex, hobbling,
   hurt, hurting, impair, impairment, incapacitation, infect,
   infringement, injure, injury, inroad, jinx, lash, loss, maiming,
   maltreat, mayhem, menace, mischief, mistreat, molest, mutilation,
   outrage, persecute, play havoc with, play hob with, poison,
   pollute, prejudice, roast, ruination, ruinousness, sabotage,
   savage, scarify, scorch, scourge, sickening, skin alive, slash,
   spoiling, taint, threaten, torment, torture, trounce, violate,
   weakening, wound, wreak havoc on, wrong