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]