Eclipse error: indirectly referenced from required .class files?

Question

I got an error in Eclipse. What does this error message means:

The type iglu.ir.TermVector cannot be resolved. It is indirectly referenced from required .class files

Answer 1

It means: "A class that you use needs another class that is not on the classpath." You should make sure (as Harry Joy suggests) to add the required jar to the classpath.