What is the green leafy vegetables used in hamburgers called?

There isn't a specific "green leafy vegetable" that's *universally* used in hamburgers.

However, there are a few popular options that people often use:

* Lettuce: The most common choice, usually in the form of crisphead, iceberg, or romaine lettuce.

* Spinach: A more nutritious option, often used in a wilted form.

* Arugula: Adds a peppery kick to the burger.

* Cabbage: Often used as coleslaw, which can be a topping for burgers.

It's really up to personal preference and the style of the burger!