The Collaborative International Dictionary of English v.0.48:

Rostrum \Ros"trum\ (-tr[u^]m), n.; pl. L. Rostra, E.
   Rostrums. [L., beak, ship's beak, fr. rodere, rosum, to
   gnaw. See Rodent.]
   1. The beak or head of a ship.
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   2. pl. (Rostra) (Rom. Antiq.) The Beaks; the stage or
      platform in the forum where orations, pleadings, funeral
      harangues, etc., were delivered; -- so called because
      after the Latin war, it was adorned with the beaks of
      captured vessels; later, applied also to other platforms
      erected in Rome for the use of public orators.
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   3. Hence, a stage for public speaking; the pulpit or platform
      occupied by an orator or public speaker.
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            Myself will mount the rostrum in his favor.
                                                  --Addison.
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   4. (Zool.)
      (a) Any beaklike prolongation, esp. of the head of an
          animal, as the beak of birds.
      (b) The beak, or sucking mouth parts, of Hemiptera.
      (c) The snout of a gastropod mollusk. See Illust. of
          Littorina.
      (d) The anterior, often spinelike, prolongation of the
          carapace of a crustacean, as in the lobster and the
          prawn.
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   5. (Bot.) Same as Rostellum.
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   6. (Old Chem.) The pipe to convey the distilling liquor into
      its receiver in the common alembic. --Quincy.
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   7. (Surg.) A pair of forceps of various kinds, having a
      beaklike form. [Obs.] --Coxe.
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