WHY DO THEY CALL IT HONEYMOON?

In many parts of Europe it was traditional to supply a newly married couple with enough mead for a month, ensuring happiness and fertility. Mead is an alcoholic beverage made from fermented honey.

From this practice we get honeymoon (moon meaning "month") or, as the French say, "lune de miel"

The Merriam-Webster dictionary reports the etymology as from "the idea that the first month of marriage is the sweetest".

One of the more recent citations in the Oxford English Dictionary indicates that, while today honeymoon has a positive meaning, the word was originally a reference to the inevitable waning of love like a phase of the moon.
Source(s):
http://en.wikipedia.org/wiki/Honeymoon

(taken from : http://answers.yahoo.com/question/index?qid=20100321212119AAdIxi4)