The Collaborative International Dictionary of English v.0.48:

Foumart \Fou"mart`\, n. [OE. folmard, fulmard; AS. f[=u]l foul +
   mear[eth], meard, marten: cf. F. marte, martre. See Foul,
   a., and Marten the quadruped.] (Zool.)
   The European polecat; -- called also European ferret, and
   fitchew. See Polecat. [Written also foulmart,
   foulimart, and fulimart.]
   [1913 Webster]