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invasion (e.g. of a country); raid; aggression
その国は隣国への侵略を開始して戦争が勃発した。
That country started an invasion of its neighbor and war broke out.
侵略行為は国際法で厳しく禁じられているはずだ。
Acts of aggression should be strictly prohibited by international law.
歴史の授業で植民地侵略について学ぶ機会があった。
I had the opportunity to learn about colonial invasion in history class.