a flat round cake of minced beef, fried or grilled and typically served in a bread roll garnished with various condiments. A hamburger (also burger for short) is a sandwich consisting of one or more cooked patties of ground meat, usually beef, placed inside a sliced bread roll or bun. The hamburger first appeared in the 19th or early 20th century. They served hot dogs and hamburgers at the cookout. Hamburger definition, a sandwich consisting of a cooked patty of ground or chopped beef, usually in a roll or bun, variously garnished.