For me personally, when I use the term "free will", I mean something stronger than "deterministic, but not provably so". That's more of a "free will of the gaps" - claiming that free will is hiding somewhere in the holes in our knowledge.
Either the things in our brains follow deterministic patterns or they're random. Neither one of those gives me room to decide to get a glass of orange juice. In fact, any desire I have at all for an orange is dependent on that type of plant having emerged billions of years ago. I can imagine a fruit that doesn't exist, but I can't desire it and I can't buy it at the store. I had no say in any part of that causal chain whatsoever.
... but of course that gets us no closer to a definition. If someone can come up with a sensible definition, it could be interesting, certainly.
b) Unlike matter and energy, information complexity does not obey laws of conservation. (Demonstrably so.)
c) Ergo, an information complexity singularity can exist, and if it does - we would be reasonably correct in calling it "free will".