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self-defense; self-defence
自衛のために武術を習い始めた人も多いらしい。
It seems many people have started learning martial arts for self-defense.
自衛隊が災害救助に出動したというニュースを見た。
I saw news that the Self-Defense Forces were dispatched for disaster relief.
自衛の手段として防犯グッズを持ち歩いているよ。
I carry security goods as a means of self-defense.