The Collaborative International Dictionary of English v.0.48:

Russ \Russ\, n. sing. & pl.
   1. A Russian, or the Russians. [Rare, except in poetry.]
      [1913 Webster]

   2. The language of the Russians.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Russ \Russ\, a.
   Of or pertaining to the Russians.
   [1913 Webster]