The Collaborative International Dictionary of English v.0.48:

Torsk \Torsk\, n. [Dan.; akin to Icel. [thorn]orskr a codfish,
   G. dorsch.] (Zool.)
   (a) The cusk. See Cusk.
   (b) The codfish. Called also tusk.
       [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tusk \Tusk\ (t[u^]sk), n. (Zool.)
   Same as Torsk.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tusk \Tusk\, n. [OE. tusk, the same word as tusch, AS. tusc. See
   Tush a tooth.]
   1. (Zool.) One of the elongated incisor or canine teeth of
      the wild boar, elephant, etc.; hence, any long, protruding
      tooth.
      [1913 Webster]

   2. (Zool.) A toothshell, or Dentalium; -- called also
      tusk-shell.
      [1913 Webster]

   3. (Carp.) A projecting member like a tenon, and serving the
      same or a similar purpose, but composed of several steps,
      or offsets. Thus, in the illustration, a is the tusk, and
      each of the several parts, or offsets, is called a tooth.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tusk \Tusk\ (t[u^]sk), v. i.
   To bare or gnash the teeth. [Obs.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Cusk \Cusk\ (k[u^]sk), n. (Zool.)
   A large, edible, marine fish (Brosmius brosme), allied to
   the cod, common on the northern coasts of Europe and America;
   -- called also tusk and torsk.
   [1913 Webster]

WordNet (r) 3.0 (2006):

tusk
    n 1: a hard smooth ivory colored dentine that makes up most of
         the tusks of elephants and walruses [syn: ivory, tusk]
    2: a long pointed tooth specialized for fighting or digging;
       especially in an elephant or walrus or hog
    v 1: stab or pierce with a horn or tusk; "the rhino horned the
         explorer" [syn: horn, tusk]
    2: remove the tusks of animals; "tusk an elephant" [syn: tusk,
       detusk]

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "tusk":
   baby tooth, bicuspid, bucktooth, canine, crown, cuspid, cutter,
   deciduous tooth, dent, denticle, denticulation, dentil, dentition,
   dogtooth, eyetooth, fang, fore tooth, gagtooth, gang tooth,
   gold tooth, gore, grinder, horn, incisor, milk tooth, molar, peg,
   permanent tooth, pivot tooth, premolar, scrivello, snag,
   snaggletooth, tooth, tush, wisdom tooth