Sienna

from WordNet (r) 3.0 (2006)

sienna
    n 1: an earth color containing ferric oxides; used as a pigment

from The Collaborative International Dictionary of English v.0.48

Sienna \Si*en"na\, n. [It. terra di Siena, fr. Siena in Italy.]
   (Chem.)
   Clay that is colored red or brown by the oxides of iron or
   manganese, and used as a pigment. It is used either in the
   raw state or burnt.
   [1913 Webster]

   {Burnt sienna}, sienna made of a much redder color by the
      action of fire.

   {Raw sienna}, sienna in its natural state, of a transparent
      yellowish brown color.
      [1913 Webster]