U-boat

2 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Submarine \Sub`ma*rine"\, n.
     1. A submarine boat; a ship that can travel under the surface
        of the water. Most such ships are ships of war, as part of
        a navy, but submarines are also used for oceanic research.
        Also called {sub} and (from the German U-Boot) {U-boat}.
        esp., Nav., a submarine torpedo boat; -- called specif.


        {submergible submarine} when capable of operating at
        various depths and of traveling considerable distances
        under water, and {submersible submarine} when capable of
        being only partly submerged, i.e., so that the conning
        tower, etc., is still above water. The latter type and
        most of the former type are submerged as desired by
        regulating the amount of water admitted to the ballast
        tanks and sink on an even keel; some of the former type
        effect submersion while under way by means of horizontal
        rudders, in some cases also with admission of water to the
        ballast tanks.
        [Webster 1913 Suppl. +PJC]
  
     2. A stowaway on a seagoing vessel. [Colloq.]
        [PJC]
  
     3. A {submarine sandwich}.
        [PJC]

From WordNet (r) 2.0 [wn]:

  U-boat
       n : a submersible warship usually armed with torpedoes [syn: {submarine},
            {pigboat}, {sub}]