That's what distinguishes determinism from my definition of free will, namely: "not determinism".
Fixed that for you
It's a bad choice of identifier for this definition though, since the words are already in use.
That "you" would be able to predict someones actions in a deterministic universe is a really misleading intuition pump. As has been mentioned by another poster, that's wildly impossible for several physical reasons. Some abstruse godlike entity would be able to simulate our actions - that hardly makes them less free.