The definition of fun is something that brings pleasure, joy or playfulness.(noun)
See fun in Webster's New World College Dictionary
Origin: < ME fonne, a fool, foolish, or fonnen, to be foolish < ?
See fun in American Heritage Dictionary 4
Origin: Possibly from fon, to make a fool of
Origin: , from Middle English fonnen, to fool
Origin: , possibly from fonne, fool. Usage Note: The use of fun as an attributive adjective, as in a fun time, a fun place, probably originated in a playful reanalysis of the use of the word in sentences such as It is fun to ski, where fun has the syntactic function of adjectives such as amusing or enjoyable. The usage became popular in the 1950s and 1960s, though there is some evidence to suggest that it has 19th-century antecedents, but it can still raise eyebrows among traditionalists. The day may come when this usage is entirely unremarkable, but writers may want to avoid it in more formal contexts.
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