Wealth, in the traditional, economic sense is all about owning shit that's valuable and leveraging it. Yes, of course, there are many definitions of wealth, like having the luxury of time or having fulfilling relationships, but I'm talking pure economics here. Ultimately, owning valuable things allows you to sell, rent or lend the value in exchange for resources, like money.
Wealth is having more resources than you need for the present and future. And having more than what you need helps quell any anxiety you might have about the relative present and the future.