The Collaborative International Dictionary of English v.0.48:

Salmon \Salm"on\ (s[a^]m"[u^]n), n.; pl. Salmons (-[u^]nz) or
   (collectively) Salmon. [OE. saumoun, salmon, F. saumon, fr.
   L. salmo, salmonis, perhaps from salire to leap. Cf. Sally,
   v.]
   1. (Zool.) Any one of several species of fishes of the genus
      Salmo and allied genera. The common salmon (Salmo
      salar) of Northern Europe and Eastern North America, and
      the California salmon, or quinnat, are the most important
      species. They are extensively preserved for food. See
      Quinnat.
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   Note: The salmons ascend rivers and penetrate to their head
         streams to spawn. They are remarkably strong fishes,
         and will even leap over considerable falls which lie in
         the way of their progress. The common salmon has been
         known to grow to the weight of seventy-five pounds;
         more generally it is from fifteen to twenty-five
         pounds. Young salmon are called parr, peal, smolt, and
         grilse. Among the true salmons are:

   Black salmon, or Lake salmon, the namaycush.

   Dog salmon, a salmon of Western North America
      (Oncorhynchus keta).

   Humpbacked salmon, a Pacific-coast salmon (Oncorhynchus
      gorbuscha).

   King salmon, the quinnat.

   Landlocked salmon, a variety of the common salmon (var.
      Sebago), long confined in certain lakes in consequence of
      obstructions that prevented it from returning to the sea.
      This last is called also dwarf salmon.
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   Note: Among fishes of other families which are locally and
         erroneously called salmon are: the pike perch, called
         jack salmon; the spotted, or southern, squeteague;
         the cabrilla, called kelp salmon; young pollock,
         called sea salmon; and the California yellowtail.
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   2. A reddish yellow or orange color, like the flesh of the
      salmon.
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   Salmon berry (Bot.), a large red raspberry growing from
      Alaska to California, the fruit of the Rubus Nutkanus.


   Salmon killer (Zool.), a stickleback (Gasterosteus
      cataphractus) of Western North America and Northern Asia.


   Salmon ladder, Salmon stair. See Fish ladder, under
      Fish.

   Salmon peel, a young salmon.

   Salmon pipe, a certain device for catching salmon. --Crabb.

   Salmon trout. (Zool.)
      (a) The European sea trout (Salmo trutta). It resembles
          the salmon, but is smaller, and has smaller and more
          numerous scales.
      (b) The American namaycush.
      (c) A name that is also applied locally to the adult black
          spotted trout (Salmo purpuratus), and to the steel
          head and other large trout of the Pacific coast.
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The Collaborative International Dictionary of English v.0.48:

Mykiss \My"kiss\, n. [Russ. muikize, prob. fr. a native name.]
   (Zool.)
   A salmon (Salmo mykiss, syn. Salmo purpuratus) marked
   with black spots and a red throat, found in most of the
   rivers from Alaska to the Colorado River, and in Siberia; --
   called also black-spotted trout, cutthroat trout, and
   redthroat trout.
   [Webster 1913 Suppl.]

The Collaborative International Dictionary of English v.0.48:

Trout \Trout\ (trout), n. [AS. truht, L. tructa, tructus; akin
   to Gr. trw`kths a sea fish with sharp teeth, fr. trw`gein to
   gnaw.]
   1. (Zool.) Any one of numerous species of fishes belonging to
      Salmo, Salvelinus, and allied genera of the family
      Salmonidae. They are highly esteemed as game fishes and
      for the quality of their flesh. All the species breed in
      fresh water, but after spawning many of them descend to
      the sea if they have an opportunity.
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   Note: The most important European species are the river, or
         brown, trout (Salmo fario), the salmon trout, and the
         sewen. The most important American species are the
         brook, speckled, or red-spotted, trout (Salvelinus
         fontinalis) of the Northern United States and Canada;
         the red-spotted trout, or Dolly Varden (see Malma);
         the lake trout (see Namaycush); the black-spotted,
         mountain, or silver, trout (Salmo purpuratus); the
         golden, or rainbow, trout (see under Rainbow); the
         blueback trout (see Oquassa); and the salmon trout
         (see under Salmon.) The European trout has been
         introduced into America.
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   2. (Zool.) Any one of several species of marine fishes more
      or less resembling a trout in appearance or habits, but
      not belonging to the same family, especially the
      California rock trouts, the common squeteague, and the
      southern, or spotted, squeteague; -- called also
      salt-water trout, sea trout, shad trout, and gray
      trout. See Squeteague, and Rock trout under Rock.
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   Trout perch (Zool.), a small fresh-water American fish
      (Percopsis guttatus), allied to the trout, but
      resembling a perch in its scales and mouth.
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