The Collaborative International Dictionary of English v.0.48:

Trigger \Trig"ger\, n. [For older tricker, from D. trekker, fr.
   trekken to draw, pull. See Trick, n.]
   1. A catch to hold the wheel of a carriage on a declivity.
      [1913 Webster]

   2. (Mech.) A piece, as a lever, which is connected with a
      catch or detent as a means of releasing it; especially
      (Firearms), the part of a lock which is moved by the
      finger to release the cock and discharge the piece.
      [1913 Webster]

   Trigger fish (Zool.), a large plectognath fish (Balistes
      Carolinensis or Balistes capriscus) common on the
      southern coast of the United States, and valued as a food
      fish in some localities. Its rough skin is used for
      scouring and polishing in the place of sandpaper. Called
      also leather jacket, and turbot.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Turbot \Tur"bot\, n. [F.; -- probably so named from its shape,
   and from L. turbo a top, a whirl.] (Zool.)
   (a) A large European flounder (Rhombus maximus) highly
       esteemed as a food fish. It often weighs from thirty to
       forty pounds. Its color on the upper side is brownish
       with small roundish tubercles scattered over the surface.
       The lower, or blind, side is white. Called also bannock
       fluke.
   (b) Any one of numerous species of flounders more or less
       related to the true turbots, as the American plaice, or
       summer flounder (see Flounder), the halibut, and the
       diamond flounder (Hypsopsetta guttulata) of California.
   (c) The filefish; -- so called in Bermuda.
   (d) The trigger fish.
       [1913 Webster]

   Spotted turbot. See Windowpane.
      [1913 Webster]

WordNet (r) 3.0 (2006):

turbot
    n 1: flesh of a large European flatfish
    2: a large brownish European flatfish [syn: turbot, Psetta
       maxima]