Dinner is the main meal of the day. The meal normally consists of a combination of cooked, or sometimes uncooked, proteins (meat, fish or legumes), with vegetables, and/or starch products like rice, noodles, or potatoes.

The word "dinner" comes from the French word dîner, the "chief repast (Meal) of the day", from Old French disner. A dinner can also be a more sophisticated meal, such as a banquet.

United Kingdom

In the United Kingdom, dinner traditionally meant the main meal of the day. In an agrarian society, prior to the mid-19th Century, this 'dinner' meal was eaten in the middle of the day, followed by an evening snack of leftovers, often called "tea" by upper-class families. As more middle and upper class men chose to work in offices in town, and keep their families in developing suburbs (previously a lawyer, doctor, farmer, or merchant lived and worked at home) returning home in the middle of the day for a large meal became inconvenient. By about 1860 many upper and middle class families switched their meal times somewhat...ladies at home would take a small mid-day meal called 'luncheon', followed by an early afternoon snack called "tea," (also the children's meal time before bed), and then have a large 'dinner' meal when the man of the house got home from work...often with invited guests. Large formal evening meals were invariably described as 'dinners' (hence, also, the term dinner jacket which is a form of evening dress). Since farm families and working class people still most often worked from home, their meal times did not change as rapidly, and they continued to eat the main meal in the middle of the day, their 'dinner,' followed by a light early evening meal 'tea.' Because of these differences in custom depending on class, 'dinner' might mean the evening meal (typically used by upper class people), or the midday meal (typically used by working class people, who describe their evening meal as 'tea'). Vestiges of the English class system remain in the choice of word one uses for the evening meal - a person with upper-class antecedents might use neither "dinner" nor "tea" but, confusingly, "supper." "Supper" traditionally meant a late night meal following a gathering. A ball or party that lasted into the early hours of the morning would often be followed by a "supper," and some people in the North use the word 'supper' to refer to a hot, often milky, drink such as cocoa or hot chocolate and biscuits, taken immediately before retiring for the night.

School dinners is a British phrase for school lunches – reflecting the fact that such school meals were originally provided chiefly for the children of the working class, who typically had their main meal in the middle of the day – and women working in school canteens are generally known in the UK as dinner ladies (however, if a pupil brings his or her food from home, it is a packed lunch).