a big headache

基本解释

They know a Lehman bankruptcy would be a big headache come Monday when the credit markets freeze up.
他们知道，在信贷市场冰封之际，下周一雷曼兄弟破产的消息会给市场带来重大冲击。
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All of this is a big headache for the central government, which is aiming to keep property affordable for the masses.
这些对于中央政府来说是个大难题，后者的目标是将房地产维持在大多数人能够承受的水平。
Doing so is simply a big headache -- or multiple headaches, rather, with names like multibrowser support, data marshaling, concurrency violation, server load, and custom servlets and servlet filters.
这么做只会带来更大的麻烦（更确切地说，是更多的麻烦），比如多浏览器支持、数据封送处理、并发冲突、服务器负载以及定制 servlet 和 servlet 过滤器。

But whatever the eventual outcome, the company could be left with a big headache.
ECONOMIST: The workers may be biting off more than they can chew
Ms. MITCHELL: This was basically a learning process for me, and it also was a big headache.
NPR: New Century's Borrowers Worry for Homes
If Mr Reinfeldt cannot secure a reliable majority in parliament, dealing with the SD could become a big headache.
ECONOMIST: The far right emerge as the big winners in Sweden’s election