What does "tusk" mean?

Tusk: (Zoöl.) One of the elongated incisor or canine teeth of the wild boar, elephant, etc.; hence, any long, protruding tooth.

Additional senses

  1. 2.(Zoöl.) A toothshell, or Dentalium; -- called also tusk-shell.
  2. 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.
  3. 4.To bare or gnash the teeth. [Obs.]

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