Definition of "Fun" :
noun: activities that are enjoyable or amusing
"I do it for the fun of it."
noun: violent and excited activity
"She asked for money and then the fun began."
noun: a disposition to find (or make) causes for amusement
"He was fun to be with."
noun: verbal wit or mockery (often at another's expense but not to be taken seriously)
"He became a figure of fun."