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to one's heart's content; as much as one wants; as hard as one can; with all one's strength; to the best of one's ability; to the utmost; with determination; hard; heavily
resolution; decisiveness; determination; resignation
思いっ切り深呼吸をしてリラックスしてみよう。
Let's try taking a deep breath with all our might.
彼は思いっ切りボールを遠くへ投げた。
He threw the ball with all his might.
思いっ切り笑ってストレス発散した。
I relieved stress by laughing heartily.