The Collaborative International Dictionary of English v.0.48:

Tussah silk \Tus"sah silk`\ [Probably fr. Hind. tasar a shuttle,
   Skr. tasara, trasara.]
   (a) A silk cloth made from the cocoons of a caterpillar other
       than the common silkworm, much used in Bengal and China.
   (b) The silk fiber itself. [Written also tusseh silk.]
       [1913 Webster]