Used as a colloquial prefix meaning 'complete' or 'utterly' in compounds (e.g., big win, crushing defeat, huge profit).
今年の試合は相手にぼろ勝ちした。
We won a crushing victory in this year's match.
彼は株でぼろ儲けして高級車を買った。
He made a huge profit in stocks and bought a luxury car.
予選で彼女は経験豊富な選手にぼろ負けした。
In the qualifying round she was soundly defeated by the experienced player.