The Collaborative International Dictionary of English v.0.48:

Emaciate \E*ma"ci*ate\, a. [L. emaciatus, p. p.]
   Emaciated. "Emaciate steeds." --T. Warton.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Emaciate \E*ma"ci*ate\, v. i. [imp. & p. p. Emaciated; p. pr.
   & vb. n. Emaciating.] [L. emaciatus, p. p. of emaciare to
   make lean; e + maciare to make lean or meager, fr. macies
   leanness, akin to macer lean. See Meager.]
   To lose flesh gradually and become very lean; to waste away
   in flesh. "He emaciated and pined away." --Sir T. Browne.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Emaciate \E*ma"ci*ate\, v. t.
   To cause to waste away in flesh and become very lean; as, his
   sickness emaciated him.
   [1913 Webster]

WordNet (r) 3.0 (2006):

emaciate
    v 1: cause to grow thin or weak; "The treatment emaciated him"
         [syn: waste, emaciate, macerate]
    2: grow weak and thin or waste away physically; "She emaciated
       during the chemotherapy"

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "emaciate":
   Sanforize, atrophy, attenuate, consume, consume away, dilute,
   dribble away, dry up, emacerate, macerate, parch, pine away,
   preshrink, rarefy, run to seed, run to waste, sear, shrink,
   shrivel, subtilize, thin, thin away, thin down, thin out, waste,
   waste away, water, water down, weaken, weazen, wither, wither away,
   wizen