プログレッシブ和英中辞典(第4版)の解説
きゅうへん【急変】
❶〔激変〕a sudden change [turn]
父の容態が急変した
My father's condition took a sudden turn for the worse.
彼の態度は急変した
His attitude changed suddenly.
❷〔緊急事態〕an emergency；〔不慮の出来事〕a contingency
急変に備えて航空母艦が派遣された
An aircraft carrier was dispatched in readiness for 「an emergency [any contingency].