Source : Webster's Revised Unabridged Dictionary (1913)

Dredge \Dredge\, v. t. [imp. & p. p. {Dredged}; p. pr. & vb. n.
   {Dredging}.]
   To catch or gather with a dredge; to deepen with a dredging
   machine. --R. Carew.

   {Dredging machine}, a machine (commonly on a boat) used to
      scoop up mud, gravel, or obstructions from the bottom of
      rivers, docks, etc., so as to deepen them.