I think the product looks awesome and it is really helpful. In the long run, I'd say that I'm missing 2 things:
1. It is not required to add references right now. I'd definitely make these mandatory, so when someone checks out a definition, they can read more and also be sure that the definition comes from a safe place.
2. I think the site lacks some community features right now - e.g., commenting and discussing topics together.
Thanks for the great review, Fanni! Much appreciated. For your first point, there are recommended resources at the bottom of each keyword :) Your second point is coming up. So stay tuned!