Yet it niggled away as I tried to catch up with the rest of the traffic.

Questions she had tried repeatedly to dismiss but which kept returning to niggle away at her irma resolution.

I reckon that Vimes character will niggle away at something like that.

It is a troubling question that niggles away throughout our visit.

The thought of not seeing him again had been niggling away at the back of her mind in a most unpleasant manner.

"He'll niggle away until he turns up every discrepancy, and in the end he'll see that somewhere around twenty-four thousand cattle have disappeared."

It's been niggling away since the start, and I can't nail it down.

But there was something that niggled away at him.

And yet there was something just something, niggling away at her.

Michael Banks's death niggled away at Charles like a hole in the tooth.