There are event you can predict on that even though it's not 💯 guaranteed that you're going to win, a level of certainty makes you think that you're surely going to win.
The downside of that feeling is that you might become over confident to use a big amount in the game since you're to a large extent certain that you're going to win.
Can we still say we are gambling if the event is something we are at least 90% sure that we are going to win?
Yes, of course, such scenario can definitely be called gambling, because inasmuch as you are not 100% sure that the outcome will be exactly just as you predicted, and their exist an atom of doubt in you that maybe this game you just predicted, may not happen exactly. Because however, I have also seen many game with a 99% success rate still fails to play, not to talkless of mere just 90% success rate. While secondly, despite how a game looks so appealing to play, it is never advisable you gamble more than you can always afford to lose.