The Collaborative International Dictionary of English v.0.48:

Sphacelate \Sphac"e*late\, v. i. [imp. & p. p. Sphacelated; p.
   pr. & vb. n. Sphacelating.] [NL. sphacelare, sphacelatum,
   mortify: cf. F. sphac['e]ler. See Sphacelus.] (Med.)
   To die, decay, or become gangrenous, as flesh or bone; to
   mortify.
   [1913 Webster]