naval ram
underwater prolongation (usually 2–4 m) of the bow of a ship that can be driven into an enemy ship to sink or disable it
en-US/ˈneɪvəl ˈɹæm/
en-GB/ˈneɪvl ˈɹæm/
underwater prolongation (usually 2–4 m) of the bow of a ship that can be driven into an enemy ship to sink or disable it