Your definition is generally inline with mine. The small exception is you can retry as many times as you can, once the desired state is reached, the result is the same after that no matter how many times you keep trying.

Using the example given, I (as producer) can retry the message however many times, the response I get should be the same. Implementation detail usually involves some kind of ID so downstream consumers know that they have process the said ID.

I do not believe if there is an exception, then future retry produce exception as well. But perhaps I misread your example.