Definition
Something niggling is persistently bothersome or annoying. It's that little itch you can't quite scratch, or a minor problem that keeps resurfacing. 'Niggling' things are often small individually, but their constant presence can be extremely irritating. Think of a dripping faucet or a persistent, low-level headache. These issues might not be serious, but they wear you down over time. They distract and prevent you from fully focusing.