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tremendous; huge; resounding
Note: prefix; usually found in compounds such as ぼろ勝ち or ぼろ儲け
そのチームは決勝でぼろ勝ちした。
That team won the final by a huge margin.
新商品が予想以上に売れてぼろ儲けした。
The new product sold far better than expected and brought in a huge profit.
序盤からミスが続いてぼろ負けした。
We kept making mistakes from the start and lost badly.