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very great; enormous; serious
甚大な被害をもたらした台風が上陸した。
A typhoon that caused enormous damage made landfall.
その事故が国全体に与えた損害は甚大だった。
The damage the accident caused to the entire country was enormous.
年金制度の崩壊は社会に甚大な影響を与えかねない。
The collapse of the pension system could have a devastating impact on society.