Jane's Aerospace Dictionary does not mention co-rotating propellers, which makes it doubtful whether it is a good term to use. It does however mention co-rotating wheels, as "wheels on live axle and thus constrained to rotate together".
In my mind, co-rotating would in fact mean a single spool arrangement. I e, if one rotates so does the other, same direction and speed. I do not believe that is what the JAA means though, but I think it is established that they'll be turning the same way.
Cheers,
Fred