[] to rapidly grow or increase in number, especially when this is a bad thing 迅速增长；快速增加◆We expect the market to mushroom in the next two years. 我们预期在今後两年内市场将会迅速繁荣。◆Pre-tax losses for the six months to 31 October mushroomed to $264 000 from $69 000. 截至 10 月 31 日，六个月以来的税前亏损额从 6.9 万元迅速增加至 26.4 万元。◆mushrooming costs 迅速增加的成本