What's the term for an isolated set of references?

Question

I know I learnt this on the SCJP syllabus, but it escapes me.

What's the term for a set of objects that refer to each other but are no longer accessible from your program (and are thus eligible for garbage collection)?

Answer 1

Your objects are unreachable (i.e. they cannot be reached from any current stack frame and can thus be considered to be garbage). In the specific case of a set of mutually-referencing objects, these can be said to have cyclic references

Answer 2

Island of Isolation