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to be dispelled (of doubts, ill feeling, etc.); to disappear; to be put behind one
to burst (of a boil, abscess, etc.)
彼女はやっと過去をふっ切れた。
She finally put the past behind her.
迷いがふっ切れて気持ちが軽くなる。
The doubts were dispelled and I feel lighter.
この件はふっ切れることにしよう。
Let us put this matter behind us.