defense – n. the act of defending someone or something from attack
navigation – n. the act of moving in a boat or ship over an area of water
nautical – adj. relating to ships and sailing
trillion – n. one thousand billion
murky – adj. very dark or foggy
maritime – adj. relating to sailing on the sea or doing business by sea
patrols – n. the act of walking or going around or through an area, building, etc., in order to make sure that it is safe