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?
I think you answered your own question- even if there is a high chance of
CERTAINTY that you will going to win, it is still considered gambling UNLESS the result is absolute.
Gambling is a game of chance. You are pretty much aware that even the slightest odds of winning may be in or against your favor depending on your general luck. So even if you argue that a person has 90% chance of winning, never discount the possibility of that 10% even if the odds are still 99% against 1.
At the end of the day, gambling is all about luck. What gives gambling the sensation of anxiety and adrenaline is its nature of not being absolute but random. Even if the odds may be in your favour, nothing is still absolute in this environment.