The Collaborative International Dictionary of English v.0.48:

Trident \Tri"dent\ (tr[imac]"dent), n. [L. tridens, -entis; tri-
   (see Tri-) + dens tooth: cf. F. trident. See Tooth.]
   1. (Class Myth.) A kind of scepter or spear with three
      prongs, -- the common attribute of Neptune.
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   2. (Rom. Antiq.) A three-pronged spear or goad, used for
      urging horses; also, the weapon used by one class of
      gladiators.
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   3. A three-pronged fish spear.
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   4. (Geom.) A curve of third order, having three infinite
      branches in one direction and a fourth infinite branch in
      the opposite direction.
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   Trident bat (Zool.), an Asiatic rhinolophid bat (Triaenops
      Persicus), having the nose membrane in the shape of a
      trident.
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