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?
The 10% left is enough to make us lose so it is still gambling. Even if the gambler is 100% sure it is still gambling since something is always at stake. It is the confidence that always make a gambler wants to gamble. Just as the gambler would want to stake high if he is sure to win so also it will be for the gambler not to stake if he is also sure that he has a zero chance of winning. It will not even be reasonable for a gambler to decide to lose when it will be safer for him to ignore gambling at that particular session.
On some occasions a gambler would be afraid to place a stake due to fear and uncertainty and at the end the game will play and he will regret not playing the game. Others times, a gambler would be confidence and certain that he will win but end up losing. Regardless of how certain a gambler is there is always no winning guarantee and that is what makes it gambling. If gamblers starts winning everyday the bookies will close down and that is why gambling is always in the bookies favour to ensure that they profit continuously and remain in the market.