Problem (noun)

1. An issue or situation that is difficult to resolve.
2. A matter or situation that requires a solution.
3. A source of difficulty or annoyance.

Origin:

From middle english problem, from latin problēma.

Examples:

1. The problem with the car is that it won't start.
2. He faced a problem at work that he couldn't solve.
3. She solved the problem by thinking outside the box.
4. The problem was complicated and required a lot of attention.
5. The problem of poverty is a global issue.