Source : Webster's Revised Unabridged Dictionary (1913)

Waste \Waste\, v. t. [imp. & p. p. {Wasted}; p. pr. & vb. n.
   {Wasting}.] [OE. wasten, OF. waster, guaster, gaster, F.
   g[^a]ter to spoil, L. vastare to devastate, to lay waste, fr.
   vastus waste, desert, uncultivated, ravaged, vast, but
   influenced by a kindred German word; cf. OHG. wuosten, G.
   w["u]sten, AS. w[=e]stan. See {Waste}, a.]
   1. To bring to ruin; to devastate; to desolate; to destroy.

            Thou barren ground, whom winter's wrath hath wasted,
            Art made a mirror to behold my plight. --Spenser.

            The Tiber Insults our walls, and wastes our fruitful
            grounds.                              --Dryden.

   2. To wear away by degrees; to impair gradually; to diminish
      by constant loss; to use up; to consume; to spend; to wear
      out.

            Until your carcasses be wasted in the wilderness.
                                                  --Num. xiv.
                                                  33.

            O, were I able To waste it all myself, and leave ye
            none!                                 --Milton.

            Here condemned To waste eternal days in woe and
            pain.                                 --Milton.

            Wasted by such a course of life, the infirmities of
            age daily grew on him.                --Robertson.

   3. To spend unnecessarily or carelessly; to employ
      prodigally; to expend without valuable result; to apply to
      useless purposes; to lavish vainly; to squander; to cause
      to be lost; to destroy by scattering or injury.

            The younger son gathered all together, and . . .
            wasted his substance with riotous living. --Luke xv.
                                                  13.

            Full many a flower is born to blush unseen, And
            waste its sweetness on the desert air. --Gray.

   4. (Law) To damage, impair, or injure, as an estate,
      voluntarily, or by suffering the buildings, fences, etc.,
      to go to decay.

   Syn: To squander; dissipate; lavish; desolate.

Wasting \Wast"ing\, a.
   Causing waste; also, undergoing waste; diminishing; as, a
   wasting disease; a wasting fortune.

Source : WordNet®

wasting
     n 1: any general reduction in vitality and strength of body and
          mind resulting from a debilitating chronic disease [syn:
           {cachexia}, {cachexy}]
     2: a decrease in size of an organ caused by disease or disuse
        [syn: {atrophy}, {wasting away}]