cassette

The word casserole derives from French casserole, which was borrowed from Old Provençal cassola, itself from Medieval Latin cattia or catia (a ladle, a small pan, a dipper), which came from ancient Greek kyathos (κύαθος), a small cup or ladle used to draw wine from a mixing bowl. The Greek kyathos became the Latin cyathus (a small measuring cup), then passed into medieval Latin as cattia (a pan or pot), into Old Provençal as cassola (a cooking vessel), into French as casserole, and finally into English in the early 18th century. The word describes the container, not the contents — a casserole is, at its etymological root, a dish, specifically a deep dish suitable for slow cooking in the oven.

The principle behind casserole cooking — slow cooking in a covered vessel where the food braises in its own juices and any added liquid — is ancient and nearly universal. Every culture has a version: the Moroccan tagine, the Roman olla, the Chinese sand pot, the Japanese donabe. What makes the French casserole historically significant is the French culinary tradition's formalization of it as a technique and the word's subsequent globalization through French culinary influence. Casserole dishes (the vessels) became standard in 18th-century French middle-class kitchens, and recipes for 'casseroles' appear in the cookbooks of that period describing both the technique and the specific dishes made with it.

In American English, 'casserole' acquired a very specific cultural meaning in the 20th century: the covered baking dish of the American potluck and suburban kitchen, typically involving protein, starch, vegetable, and a binding sauce, often with a breadcrumb or cheese topping. The Green Bean Casserole — created by Dorcas Reilly at Campbell Soup Company in 1955, combining canned green beans, Campbell's cream of mushroom soup, and French's fried onions — is perhaps the most consumed casserole in American history. Roughly 40 million of them are made at Thanksgiving each year. The ancient Greek ladle's descendant became one of America's most popular convenience foods.

The word casserole now does double duty in English: it names both the vessel (a casserole dish, an oven-safe covered baking dish) and the food prepared in it (a casserole, typically a one-pot oven-baked preparation of combined ingredients). This conflation of container and contents is a natural development — when a vessel is so closely associated with a particular type of cooking, the dish takes the name of the pot. The same thing happened with chowder (from the cauldron chaudière), with wok (the Chinese pan gives its name to wok-cooked dishes), and with casserole, where the Greek ladle became an American Thanksgiving institution.