The Collaborative International Dictionary of English v.0.48:

Tumefy \Tu"me*fy\ (t[=u]"m[-e]*f[imac]), v. t. [imp. & p. p.
   Tumefied (t[=u]"m[-e]*f[imac]d); p. pr. & vb. n.
   Tumefying.] [F. tum['e]fier, fr. L. tumere to swell +
   -ficare (in comp.) to make; cf. L. tumefacere to tumefy. See
   Tumid, and -fy.]
   To swell; to cause to swell, or puff up.
   [1913 Webster]

         To swell, tumefy, stiffen, not the diction only, but
         the tenor of the thought.                --De Quincey.
   [1913 Webster]