noun
nuclear submarine
A submarine powered by a nuclear reactor. Used in military and technical contexts.
原子力潜水艦は長期間潜航できる。
Nuclear submarines can stay submerged for long periods.
General term for 'submarine'; 原子力潜水艦 specifies nuclear-powered ones.
Compound of 原子力 (nuclear power) + 潜水艦 (submarine).