来自omen,预兆，预示，-ous,形容词后缀。即有预兆的，在早期也可指吉兆，现仅用来指凶兆，不祥的。

1. The rolls of distant thunder were growing more ominous.

远处隆隆的雷声听着愈发惊心，要变天了。

来自柯林斯例句

2. It's an ominous development that may bode ill for the Russian parliament.

进展很不顺利，对俄罗斯议会来说这可能是个坏兆头。

来自柯林斯例句

3. This ominous warning soon proved prophetic.

这个不祥的警告很快证明是有预见性的。

来自柯林斯例句

4. There were ominous dark clouds gathering overhead.

不祥的阴霾在头顶上汇聚。

来自《权威词典》

5. Those black clouds look ominous for our picnic.

那些乌云对我们的野餐来说是个不祥之兆.

来自《简明英汉词典》