There was also a nagging worry that he couldn't quite pin down.

Something was disturbing him, like a nagging worry at the back of his mind.

Her last thought was a nagging worry about why she should be so utterly exhausted.

At the same time, he had a nagging worry.

I hardly thought so but the possibility was a nagging worry.

No matter how hard she tried to concentrate on that nagging worry, another thought was pushing it out of her mind.

For now, the woman is happy to be leaving, but there is a nagging worry.

The loss of hydraulic pressure was a nagging worry, though.

This makes it difficult to reach a decision, and causes a nagging worry as to whether the right system has been selected.

I have a nagging worry that such intervention may not be the solution.