Source : Webster's Revised Unabridged Dictionary (1913)

Imbrown \Im*brown"\, v. t. [Pref. im- in + brown. Cf.
   {Embrown}.]
   To make brown; to obscure; to darken; to tan; as, features
   imbrowned by exposure.

         The mountain mass by scorching skies imbrowned.
                                                  --Byron.