The Collaborative International Dictionary of English v.0.48:

Adipocere \Ad"i*po*cere`\, n. [L. adeps, adipis, fat + cera wax:
   cf. F. adipocere.]
   A soft, unctuous, or waxy substance, of a light brown color,
   into which the fat and muscle tissue of dead bodies sometimes
   are converted, by long immersion in water or by burial in
   moist places. It is a result of fatty degeneration.
   [1913 Webster]