形容词形式是disastrous，例如：

1、If word got out now， a scandal could be disastrous如果消息现在传出去，可能会是灾难性的丑闻。

2、This had been a disastrous week for Prime Minister Major.这对于梅杰首相来说是灾难性的一周。

3、Last year's figures were little short of disastrous.去年的数字简直是灾难。