An idiom meaning to be excessively cautious — literally 'tap a stone bridge before crossing it.'
彼女は重要な契約の前に何度も確認する、まさに石橋を叩いて渡るタイプだ。
She double-checks everything before an important contract — truly the type to tap a stone bridge before crossing.
石橋を叩いて渡るように準備をして、トラブルを未然に防いだ。
By preparing with extreme caution, we prevented problems beforehand.
あの上司は決断前に必ずデータを確認するので、石橋を叩いて渡ると言われる。
That boss always checks the data before deciding, so people call him 'someone who taps a stone bridge before crossing.'