Source : Webster's Revised Unabridged Dictionary (1913)

Sting ray \Sting ray\ or Stingray \Sting"ray`\, n.
   Any one of numerous rays of the family {Dasyatid[ae]}, syn.
   {Trygonid[ae]}, having one or more large sharp barbed dorsal
   spines, on the whiplike tail, capable of inflicting severe
   wounds. Some species reach a large size, and some, esp., on
   the American Pacific coast, are very destructive to oysters.

Source : WordNet®

stingray
     n : large venomous ray with large barbed spines near the base of
         a thin whiplike tail capable of inflicting severe wounds