Where do the words 'lunch' and 'dinner' come from?

Lunch (as provided by dictionary.com’s Online Etimology dictionary):

“luncheon-1580, nonechenche “light mid-day meal,” from none “noon” + schench “drink,” from O.E. scenc, from scencan “pour out.” Altered by northern Eng. dial. lunch “hunk of bread or cheese” (1590), which probably is from Sp. lonja “a slice,” lit. “loin.” When it first appeared, luncheon meant “thick piece, hunk;” sense of “light repast between mealtimes” is from 1652, esp. in ref. to an early afternoon meal eaten by those who have a noontime dinner. Type of restaurant called a luncheonette is attested from 1924, Amer.Eng. Slang phrase out to lunch “insane, stupid, clueless” first recorded 1955, on notion of being “not there.”

Sources:

American Psychological Association (APA):
luncheon. (n.d.). Online Etymology Dictionary. Retrieved June 19, 2008, from http://Dictionary.com website:
http://dictionary.reference.com/browse/luncheon

Chicago Manual Style (CMS):
luncheon. http://Dictionary.com. Online Etymology Dictionary. Douglas Harper, Historian.

http://dictionary.reference.com/browse/luncheon (accessed: June 19, 2008).

Modern Language Association (MLA):
“luncheon.” Online Etymology Dictionary. Douglas Harper, Historian. 19 Jun. 2008.

Dinner (also from dictionary.com):

“Word History: Eating foods such as pizza and ice cream for breakfast may be justified etymologically. In Middle English dinner meant “breakfast,” as did the Old French word disner, or diner, which was the source of our word. The Old French word came from the Vulgar Latin word *disiūnāre, meaning “to break one’s fast; that is, to eat one’s first meal,” a notion also contained in our word breakfast. The Vulgar Latin word was derived from an earlier word, *disiēiūnāre, the Latin elements of which are dis-, denoting reversal, and iēiūnium, “fast.” Middle English diner not only meant “breakfast” but, echoing usage of the Old French word diner, more commonly meant “the first big meal of the day, usually eaten between 9 A.M. and noon.” Customs change, however, and over the years we have let the chief meal become the last meal of the day, by which time we have broken our fast more than once.”