It's a coffee bean. Espresso beans are coffee beans. Espresso just designate the type of roast.

The name of each bean signifies the type of roast that was imparted on them, thus lending them their unique characteristics. Espresso was named as such because the beans were roasted in such a way that would make for great espresso shots. It is a matter of taste. There’s no telling what makes great espresso shots in terms of flavor profiles. In that way, you can make a regular cup of coffee with espresso beans or vice versa, pull espresso shots with, say, Italian.