The Collaborative International Dictionary of English v.0.48:

Torrefy \Tor"re*fy\, v. t. [imp. & p. p. Torrefied; p. pr. &
   vb. n. Torrefying.] [L. torrere to parch + -fy: cf. F.
   torr['e]fier, L. torrefacere.] [Written also torrify.]
   1. To dry by a fire. --Sir T. Browne.
      [1913 Webster]

   2. (Metal.) To subject to scorching heat, so as to drive off
      volatile ingredients; to roast, as ores.
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   3. (Pharm.) To dry or parch, as drugs, on a metallic plate
      till they are friable, or are reduced to the state
      desired.
      [1913 Webster]