Source : Webster's Revised Unabridged Dictionary (1913)

Embrown \Em*brown"\, v. t. [Pref. em- (L. in) + brown.]
   To give a brown color to; to imbrown.

         Summer suns embrown the laboring swain.  --Fenton.

Source : WordNet®

embrown
     v 1: cause to darken
     2: make brown