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
see also:
sapped sapping 

sap
     n 1: a watery solution of sugars, salts, and minerals that
          circulates through the vascular system of a plant
     2: a person who lacks good judgment syn: fool, saphead, muggins,
         tomfool
     3: a piece of metal covered by leather with a flexible handle;
        used for hitting people syn: blackjack, cosh
     v 1: deplete; "exhaust one's savings"; "we quickly played out our
          strength" syn: run down, exhaust, play out, tire
     2: excavate the earth beneath
     also: sapping, sapped
see also:
fool saphead muggins tomfool blackjack cosh 
run down exhaust play out tire sapping 
sapped 

sapped
     see sap
see also:
sap 

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