The Collaborative International Dictionary of English v.0.48:

Bilge \Bilge\ (b[i^]lj), v. i. [imp. & p. p. Bilged
   (b[i^]ljd); p. pr. & vb. n. Bilging.]
   1. (Naut.) To suffer a fracture in the bilge; to spring a
      leak by a fracture in the bilge.
      [1913 Webster]

   2. To bulge.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bilge \Bilge\, v. t.
   1. (Naut.) To fracture the bilge of, or stave in the bottom
      of (a ship or other vessel).
      [1913 Webster]

   2. To cause to bulge.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bilge \Bilge\, n. [A different orthography of bulge, of same
   origin as belly. Cf. Belly, Bulge.]
   1. The protuberant part of a cask, which is usually in the
      middle.
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   2. (Naut.) That part of a ship's hull or bottom which is
      broadest and most nearly flat, and on which she would rest
      if aground.
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   3. Bilge water.
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   Bilge free (Naut.), stowed in such a way that the bilge is
      clear of everything; -- said of a cask.

   Bilge pump, a pump to draw the bilge water from the gold of
      a ship.

   Bilge water (Naut.), water which collects in the bilge or
      bottom of a ship or other vessel. It is often allowed to
      remain till it becomes very offensive.

   Bilge ways, the timbers which support the cradle of a ship
      upon the ways, and which slide upon the launching ways in
      launching the vessel.
      [1913 Webster]

WordNet (r) 3.0 (2006):

bilge
    n 1: water accumulated in the bilge of a ship [syn: bilge,
         bilge water]
    2: where the sides of the vessel curve in to form the bottom
    v 1: cause to leak; "the collision bilged the vessel"
    2: take in water at the bilge; "the tanker bilged" [syn:
       bilge, take in water]