The Collaborative International Dictionary of English v.0.48:

Gammoning \Gam"mon*ing\, n. [From 5th Gammon.] (Naut.)
   The lashing or iron band by which the bowsprit of a vessel is
   secured to the stem to opposite the lifting action of the
   forestays.
   [1913 Webster]

   Gammoning fashion, in the style of gammoning lashing, that
      is, having the turns of rope crossed.

   Gammoning hole (Naut.), a hole cut through the knee of the
      head of a vessel for the purpose of gammoning the
      bowsprit.
      [1913 Webster]