What is a common characteristic of all beverages labeled with the component 'Espresso'?

The characteristic that defines beverages labeled with the component 'Espresso' is that they all contain espresso as a base. Espresso is a concentrated coffee beverage brewed by forcing hot pressurized water through finely-ground coffee beans. This fundamental component is what distinguishes these drinks from others; they are typically rich in flavor and have a distinct coffee essence.

In contrast, the other characteristics mentioned do not universally apply to all espresso beverages. For example, while some espresso drinks may include steamed milk or whipped cream (such as lattes or cappuccinos), not all do. Additionally, espresso can be served in various forms, including iced drinks or blended beverages, which do not require serving hot. Thus, the inclusion of espresso as a base is the key defining feature that applies across all beverages labeled with 'Espresso.'