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decisively; decidedly; boldly; once and for all; unreservedly; frankly
precisely; exactly
彼女はずばりと核心を突いた質問をした。
She asked a question that hit right at the heart of the matter.
ずばり当ててしまって周りが驚いていた。
I guessed exactly right and everyone was surprised.
ずばり言うと、その計画は失敗するだろう。
To put it bluntly, that plan will fail.