[1] : The Collaborative International Dictionary of English v.0.48

bighorn \big"horn`\, n. zool.
   the rocky mountain sheep ovis montana or caprovis
   montana; called also bighorn sheep.
   1913 webster
see also:
ovis montana caprovis montana bighorn sheep 

[2] : WordNet (r) 2.0

bighorn sheep
     n : wild sheep of mountainous regions of western north america
         having massive curled horns syn: bighorn, cimarron,
         rocky mountain bighorn, rocky mountain sheep, ovis
         canadensis
see also:
bighorn cimarron rocky mountain bighorn rocky mountain sheep ovis canadensis 

Bighorn Sheep >> B Words
Bighorn Sheep, definition of term: Bighorn Sheep
bighorn+sheep_pag1.html

Bighorn >> B Words
Bighorn, definition of term: Bighorn
bighorn_pag1.html

Sheep >> S Words
Sheep, definition of term: Sheep
sheep_pag1.html

Sheep Sorrel >> S Words
Sheep Sorrel, definition of term: Sheep Sorrel
sheep+sorrel_pag1.html

Sheep Dip >> S Words
Sheep Dip, definition of term: Sheep Dip
sheep+dip_pag1.html

Wild Sheep >> W Words
Wild Sheep, definition of term: Wild Sheep
wild+sheep_pag1.html

Black Sheep >> B Words
Black Sheep, definition of term: Black Sheep
black+sheep_pag1.html