A hero sandwich is a large sandwich typically made by splitting a long, oblong roll—often a French or Italian bread—lengthwise and filling it with a variety of ingredients such as deli meats (like salami, prosciutto, pepperoni, mortadella, or ham), cheeses (like provolone or mozzarella), vegetables (such as lettuce and tomatoes), and condiments like mayonnaise, mustard, olive oil, or vinegar.
It is also known by various regional names across the United States, including sub, hoagie, grinder, or Italian sandwich.
The term "hero" is particularly prevalent in New York City, where it is often used to describe both cold and hot versions of the sandwich, such as meatball heroes or chicken Parmigiana heroes.