Sapped

Sap \Sap\, v. t. [imp. & p. p. {Sapped}; p. pr. & vb. n.
   {Sapping}.] [F. saper (cf. Sp. zapar, It. zapare), fr. sape a
   sort of scythe, LL. sappa a sort of mattock.]
   1. To subvert by digging or wearing away; to mine; to
      undermine; to destroy the foundation of.
      [1913 Webster]

            Nor safe their dwellings were, for sapped by floods,
            Their houses fell upon their household gods.
                                                  --Dryden.
      [1913 Webster]

   2. (Mil.) To pierce with saps.
      [1913 Webster]

   3. To make unstable or infirm; to unsettle; to weaken.
      [1913 Webster]

            Ring out the grief that saps the mind. --Tennyson.
      [1913 Webster]
    

20 Moby Thesaurus words for "sapped":
      ausgespielt, burned-out, devitalized, disabled, drained, effete,
      enervated, enfeebled, eviscerated, exhausted, fatigued,
      incapacitated, played out, run-down, spent, used up, wasted,
      weakened, worn, worn-out