The Collaborative International Dictionary of English v.0.48:
Bomb \Bomb\, n. [F. bombe bombshell, fr. L. bombus a humming or
   buzzing noise, Gr. ?.]
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   1. A great noise; a hollow sound. [Obs.]
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            A pillar of iron . . . which if you had struck,
            would make . . . a great bomb in the chamber
            beneath.                              --Bacon.
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   2. (Mil.) A shell; esp. a spherical shell, like those fired
      from mortars. See Shell.
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   3. A bomb ketch.
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   Bomb chest (Mil.), a chest filled with bombs, or only with
      gunpowder, placed under ground, to cause destruction by
      its explosion.
   Bomb ketch, Bomb vessel (Naut.), a small ketch or vessel,
      very strongly built, on which mortars are mounted to be
      used in naval bombardments; -- called also mortar
      vessel.
   Bomb lance, a lance or harpoon with an explosive head, used
      in whale fishing.
   Volcanic bomb, a mass of lava of a spherical or pear shape.
      "I noticed volcanic bombs." --Darwin.
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