The Collaborative International Dictionary of English v.0.48:

Lake \Lake\, n. [AS. lac, L. lacus; akin to AS. lagu lake, sea,
   Icel. l["o]gr; OIr. loch; cf. Gr. la`kkos pond, tank. Cf.
   Loch, Lough.]
   A large body of water contained in a depression of the
   earth's surface, and supplied from the drainage of a more or
   less extended area.
   [1913 Webster]

   Note: Lakes are for the most part of fresh water; the salt
         lakes, like the Great Salt Lake of Utah, have usually
         no outlet to the ocean.
         [1913 Webster]

   Lake dwellers (Ethnol.), people of a prehistoric race, or
      races, which inhabited different parts of Europe. Their
      dwellings were built on piles in lakes, a short distance
      from the shore. Their relics are common in the lakes of
      Switzerland.

   Lake dwellings (Archaeol.), dwellings built over a lake,
      sometimes on piles, and sometimes on rude foundations kept
      in place by piles; specifically, such dwellings of
      prehistoric times. Lake dwellings are still used by many
      savage tribes. Called also lacustrine dwellings. See
      Crannog.

   Lake fly (Zool.), any one of numerous species of dipterous
      flies of the genus Chironomus. In form they resemble
      mosquitoes, but they do not bite. The larvae live in
      lakes.

   Lake herring (Zool.), the cisco (Coregonus Artedii).

   Lake poets, Lake school, a collective name originally
      applied in contempt, but now in honor, to Southey,
      Coleridge, and Wordsworth, who lived in the lake country
      of Cumberland, England, Lamb and a few others were classed
      with these by hostile critics. Called also lakers and
      lakists.

   Lake sturgeon (Zool.), a sturgeon (Acipenser rubicundus),
      of moderate size, found in the Great Lakes and the
      Mississippi River. It is used as food.

   Lake trout (Zool.), any one of several species of trout and
      salmon; in Europe, esp. Salmo fario; in the United
      States, esp. Salvelinus namaycush of the Great Lakes,
      and of various lakes in New York, Eastern Maine, and
      Canada. A large variety of brook trout (Salvelinus
      fontinalis), inhabiting many lakes in New England, is
      also called lake trout. See Namaycush.

   Lake whitefish. (Zool.) See Whitefish.

   Lake whiting (Zool.), an American whitefish (Coregonus
      Labradoricus), found in many lakes in the Northern United
      States and Canada. It is more slender than the common
      whitefish.
      [1913 Webster]

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.
      [1913 Webster]
      [1913 Webster]

   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.
         [1913 Webster]

   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.
      [1913 Webster]

   Trout perch (Zool.), a small fresh-water American fish
      (Percopsis guttatus), allied to the trout, but
      resembling a perch in its scales and mouth.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Char \Char\, Charr \Charr\, n. [Ir. cear, Gael. ceara, lit.,
   red, blood-colored, fr. cear blood. So named from its red
   belly.] (Zool.)
   One of the several species of fishes of the genus
   Salvelinus, allied to the spotted trout and salmon,
   inhabiting deep lakes in mountainous regions in Europe. In
   the United States, the brook trout (Salvelinus fontinalis)
   is sometimes called a char.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Salvelinus fontinalis
    n 1: North American freshwater trout; introduced in Europe [syn:
         brook trout, speckled trout, Salvelinus fontinalis]