Source : Webster's Revised Unabridged Dictionary (1913)

Demephitize \De*meph"i*tize\, v. t. [imp. & p. p.
   {Demephitized}; p. pr. & vb. n. {Demephitizing}.] [Cf. F.
   m['e]phitiser to infect with mephitis.]
   To purify from mephitic or foul air. --
   {De*meph`i*ti*za"tion}, n.