#pigboat__submarine__sub__uboat  a submersible warship usually armed with torpedoes
  supertype:  submersible_warship__submersiblewarship__submersible  a warship designed to operate under water
  part:  conning_tower  escape_hatch  periscope  snorkel_breather  sonar
  subtype:  attack_submarine  a military submarine designed and armed to attack enemy shipping
  subtype:  auxiliary_research_submarine  a submarine for research purposes
  subtype:  fleet_ballistic_missile_submarine__fleetballisticmissilesubmarine  a submarine carrying ballistic missiles
  subtype:  nautilus__nuclear_submarine__nuclearsubmarine__nuclear-powered_submarine__nuclearpoweredsubmarine  a submarine that is propelled by nuclear power

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