The Collaborative International Dictionary of English v.0.48:

Shark \Shark\ (sh[aum]rk), n. [Of uncertain origin; perhaps
   through OF. fr. carcharus a kind of dogfish, Gr. karchari`as,
   so called from its sharp teeth, fr. ka`rcharos having sharp
   or jagged teeth; or perhaps named from its rapacity (cf.
   Shark, v. t. & i.); cf. Corn. scarceas.]
   1. (Zool.) Any one of numerous species of elasmobranch fishes
      of the order Plagiostomi, found in all seas.
      [1913 Webster]

   Note: Some sharks, as the basking shark and the whale shark,
         grow to an enormous size, the former becoming forty
         feet or more, and the latter sixty feet or more, in
         length. Most of them are harmless to man, but some are
         exceedingly voracious. The man-eating sharks mostly
         belong to the genera Carcharhinus, Carcharodon, and
         related genera. They have several rows of large sharp
         teeth with serrated edges, as the great white shark
         (Carcharodon carcharias or Carcharodon Rondeleti)
         of tropical seas, and the great blue shark
         (Carcharhinus glaucus syn. Prionace glauca) of all
         tropical and temperate seas. The former sometimes
         becomes thirty-six feet long, and is the most voracious
         and dangerous species known. The rare man-eating shark
         of the United States coast (Carcharodon Atwoodi) is
         thought by some to be a variety, or the young, of
         Carcharodon carcharias. The dusky shark
         (Carcharhinus obscurus) is a common species on the
         coast of the United States of moderate size and not
         dangerous. It feeds on shellfish and bottom fishes.
         [1913 Webster]

   Note: The original 1913 Webster also mentioned a "smaller
         blue shark (C. caudatus)", but this species could not
         be found mentioned on the Web (August 2002). The
         following is a list of Atlantic Ocean sharks:
         * * * * * * * * * * * * * * * *
         Common and Scientific Names of Atlantic Sharks
         * * * * * * * * * * * * * * * *
         from "Our Living Oceans 1995" (published by the
         National Printing Office):
         NMFS. 1999. Our Living Oceans. Report on the status of
         U.S. living marine resources, 1999. U.S. Dep. Commer.,
         NOAA Tech. Memo. NMFS-F/SPO-41, on-line version,
         http://spo.nwr.noaa.gov/olo99.htm.
         (the following list is found at at
         http://spo.nwr.noaa.gov/app5.pdf)
         (1) Pelagic Sharks
         Thresher shark (Alopias vulpinus)
         Bigeye thresher (Alopias superciliosus)
         Oceanic whitetip shark (Carcharhinus longimanus)
         Sevengill shark (Heptrachias perlo)
         Sixgill shark (Hexanchus griseus)
         Bigeye sixgill shark (Hexanchus vitulus)
         Shortfin mako (Isurus oxyrinchus)
         Longfin mako (Isurus paucus)
         Porbeagle (Lamna nasus)
         Blue shark (Prionace glauca)
         (2)Large Coastal Sharks
         Sandbar shark (Carcharhinus plumbeus)
         Reef shark (Carcharhinus perezi)
         Blacktip shark (Carcharhinus limbatus)
         Dusky shark (Carcharhinus obscurus)
         Spinner shark (Carcharhinus brevipinna)
         Silky shark (Carcharhinus falciformis)
         Bull shark (Carcharhinus leucas)
         Bignose shark (Carcharhinus altimus)
         Galapagos shark (Carcharhinus galapagensis)
         Night shark (Carcharhinus signatus)
         White shark (Carcharodon carcharias)
         Basking shark (Cetorhinus maximus)
         Tiger shark (Galeocerdo cuvier)
         Nurse shark (Ginglymostoma cirratum)
         Lemon shark (Negaprion brevirostris)
         Ragged-tooth shark (Odontaspis ferox)
         Whale shark (Rhincodon typus)
         Scalloped hammerhead (Sphyrna lewini)
         Great hammerhead (Sphyrna mokarran)
         Smooth hammerhead (Sphyrna zygaena)
         (3) Small Coastal Sharks
         Finetooth shark (Carcharhinus isodon)
         Blacknose shark (Carcharhinus acronotus)
         Atlantic sharpnose shark (Rhizoprionodon erraenovae)
         Caribbean sharpnose shark (Rhizoprionodon porosus)
         Bonnethead (Sphyrna tiburo)
         Atlantic angel shark (Squatina dumeril)
         [PJC]

   2. A rapacious, artful person; a sharper. [Colloq.]
      [1913 Webster]

   3. Trickery; fraud; petty rapine; as, to live upon the shark.
      [Obs.] --South.
      [1913 Webster]

   Basking shark, Liver shark, Nurse shark, Oil shark,
   Sand shark, Tiger shark, etc. See under Basking,
      Liver, etc. See also Dogfish, Houndfish,
      Notidanian, and Tope.

   Gray shark, the sand shark.

   Hammer-headed shark. See Hammerhead.

   Port Jackson shark. See Cestraciont.

   Shark barrow, the eggcase of a shark; a sea purse.

   Shark ray. Same as Angel fish
      (a), under Angel.

   Thrasher shark or Thresher shark, a large, voracious
      shark. See Thrasher.

   Whale shark, a huge harmless shark (Rhinodon typicus) of
      the Indian Ocean. It becomes sixty feet or more in length,
      but has very small teeth.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Liver \Liv"er\, n. [AS. lifer; akin to D. liver, G. leber, OHG.
   lebara, Icel. lifr, Sw. lefver, and perh. to Gr. ? fat, E.
   live, v.] (Anat.)
   A very large glandular and vascular organ in the visceral
   cavity of all vertebrates.
   [1913 Webster]

   Note: Most of the venous blood from the alimentary canal
         passes through it on its way back to the heart; and it
         secretes the bile, produces glycogen, and in other ways
         changes the blood which passes through it. In man it is
         situated immediately beneath the diaphragm and mainly
         on the right side. See Bile, Digestive, and
         Glycogen. The liver of invertebrate animals is
         usually made up of c[ae]cal tubes, and differs
         materially, in form and function, from that of
         vertebrates.
         [1913 Webster]

   Floating liver. See Wandering liver, under Wandering.


   Liver of antimony, Liver of sulphur. (Old Chem.) See
      Hepar.

   Liver brown, Liver color, the color of liver, a dark,
      reddish brown.

   Liver shark (Zool.), a very large shark (Cetorhinus
      maximus), inhabiting the northern coasts both of Europe
      and North America. It sometimes becomes forty feet in
      length, being one of the largest sharks known; but it has
      small simple teeth, and is not dangerous. It is captured
      for the sake of its liver, which often yields several
      barrels of oil. It has gill rakers, resembling whalebone,
      by means of which it separates small animals from the sea
      water. Called also basking shark, bone shark,
      hoemother, homer, and sailfish; it is sometimes
      referred to as whale shark, but that name is more
      commonly used for the Rhincodon typus, which grows even
      larger.

   Liver spots, yellowish brown patches on the skin, or spots
      of chloasma.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Basking shark \Bask"ing shark`\ (Zool.)
   One of the largest species of sharks (Cetorhinus maximus),
   so called from its habit of basking in the sun; the liver
   shark, or bone shark. It inhabits the northern seas of
   Europe and America, and grows to a length of more than forty
   feet. It is a harmless species.
   [1913 Webster]

WordNet (r) 3.0 (2006):

basking shark
    n 1: large harmless plankton-eating northern shark; often swims
         slowly or floats at the sea surface [syn: basking shark,
         Cetorhinus maximus]