These words all mean to cook food by exposing it to dry heat. Grill , which is synonymous with the American term broil, refers to the rapid cooking of small pieces of food by intense, direct heat. Fish, fowl, meat and some vegetables such as tomatoes and mushrooms are grilled. In grilling , one surface of the food is exposed to the heating source at a time. Because of the intensity of the heat these surfaces are sealed, allowing the meat, fish, etc., to retain its juices with their intrinsic flavour and nutritive value. Grilling requires the use of a grill or gridiron, which is a metal grate set in a frame. The food to be cooked is placed on this grate; the heating source is above or below the grate: to grill a chop.

Before the invention of the stove, roast meant to cook by exposure to the heat of an open fire or flame, and it usually referred to the cooking of a large piece of meat or even a whole animal or fowl: to roast a pig. Roasting was a slower process than grilling ; the food to be cooked was often placed on a spit that could be turned in order to let all sides of the food be exposed to the source of heat. Today roasting is done in an oven where the food is cooked by radiant and reflected heat and, in addition, by heat that is transferred from the pan in which the food is being cooked. This kind of roasting is faster than the older method, but is still a slower process than grilling . Roast is also used to denote the placing of food in hot ashes, embers, stones, etc., and the keeping of it there long enough for it to be cooked. And it may mean to dry and parch under the action of heat: to roast coffee; roasted peanuts.

Bake is like roast in that it refers to cooking by dry, continuous heat in an oven or similar enclosed unit. There is no difference between these two terms as far as the method of cooking is concerned. The difference between roast and bake is that the former is used almost exclusively in reference to large pieces of meat or fowl, while the latter can be applied as well to anything else that is cooked in an oven: to bake a cake; to bake fish; to bake a casserole of meat and vegetables; baked potatoes. To barbecue is to grill or roast meat (usually beef, pork or chicken) either on a spit or gridiron or else over a trench called a barbecue pit. One may barbecue meat over coals or an open fire. Modern barbecuing devices range from the small tripod type with concave hot plate, fuelled with chips or charcoal, to the rotisserie which has a gas or electrical heating unit. Barbecued food may consist of a whole animal or large pieces of one. In many cases the meat is marinated and basted with some kind of highly seasoned sauce: barbecued loin chops. As a noun, barbecue refers generally to an outdoor party at which the guests eat barbecued food: Can you come to a barbecue at our place on Saturday night?

Applied to human beings, broil and roast mean to get or be extremely hot and sweaty: travellers broiling in the sun as they cross the desert; passengers roasting in a hot car during a traffic jam. Bake may mean to tan in the sun, as while sunbathing, but usually refers to excessive exposure. In a more informal sense, roast may also mean to criticize or ridicule severely, whether in earnest or as a form of good-humoured raillery. The captain roasted his players over their dropped catches and slowness in the field.