It means "heavily discount".
Example sentence:
As holders of mortgage-backed securities and the like revalue their assets at fire-sale prices, they are running short of capital -- which can lead to further sales and more write-downs.
That's a fire sale.
This fire sale was not enough for one creditor, Merrill Lynch, which seized collateral and threatened to auction it off to cover its losses. 但这次低价甩卖对美林来说依然不够，美林声称准备将其持有的持有的担保债券拍卖，以弥补损失。