a bit of a/an
1. Somewhat; rather; to some extent. He's a nice enough guy, but he's a bit of a dolt. There's just a bit of an issue with our Wi-Fi at the moment; it should be back on in a few minutes.
2. A very considerable amount or degree. It looks to be a bit of a mess for the prime minister. We'll need a bit of planning to pull off an event this big.
a bit of a...
(informal, especially British English) used when talking about unpleasant or negative things or ideas, to mean ‘rather a...’: We may have a bit of a problem on our hands.The rail strike is a bit of a pain.