Dinner usually refers to the most significant and important meal of the day, which can be the noon or the evening meal. However, the term "dinner" can have many different meanings depending on the culture; it may mean a meal of any size eaten at any time of the day. Historically, it referred to the first meal of the day, eaten around noon, and is still sometimes used for a noon-time meal, particularly if it is a large or main meal. The meaning as the evening meal, generally the largest of the day, is becoming a standard in many parts of the English-speaking world.
The word is from the Old French (c. 1300) disner, meaning "dine", from the stem of Gallo-Romance desjunare ("to break one's fast"), from Latin dis- (which indicates the opposite of an action) + Late Latin ieiunare ("to fast"), from Latin ieiunus ("fasting, hungry"). The Romanian word dejun and the French déjeuner retain this etymology and to some extent the meaning (whereas the Spanish word desayuno and Portuguese desjejum are related but are exclusively used for breakfast). Eventually, the term shifted to referring to the heavy main meal of the day, even if it had been preceded by a breakfast meal (or even both breakfast and lunch).
In Europe, the fashionable hour for dinner began to be incrementally postponed during the 18th century, to two and three in the afternoon, until at the time of the First French Empire an English traveler to Paris remarked upon the "abominable habit of dining as late as seven in the evening".
In many modern usages, the term dinner refers to the evening meal, which is now often the most significant meal of the day in English-speaking cultures. When this meaning is used, the preceding meals are usually referred to as breakfast, lunch and tea. In some areas, the tradition of using dinner to mean the most important meal of the day regardless of time of day leads to a variable name for meals depending on the combination of their size and the time of day, while in others meal names are fixed based on the time they are consumed.