underwater
anchored
armed
army
boat
deck
deep
defence
defend
defense
diesel
fleet
force
forces
frigate
harbor
marine
metal
military
mission
modern
nato
nautical
naval
navy
navy submarine
nuclear
ocean
operation
part
patrol
periscope
profundity
radar
sea
ship
sky
steel
submarine
technology
torpedo
transport
undersea
vessel
war
warfare
warship
weapon