bull trout

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A freshwater game fish (Salvelinus confluentus) of western North America, having yellow spots on the back and red or orange spots on the sides, and resembling the Dolly Varden.

from The Century Dictionary.

• noun A name loosely applied to certain varieties of different species of the genus Salmo, as of S. salar, S. trutta, S. cambricus.
• noun Salvelinus malma, of northern and western North America and Kamchatka.

from the GNU version of the Collaborative International Dictionary of English.

• In England, a large salmon trout of several species, as Salmo trutta and Salmo Cambricus, which ascend rivers; -- called also sea trout.
• Salvelinus malma of California and Oregon; -- called also Dolly Varden trout and red-spotted trout.
• The huso or salmon of the Danube.