Webster's Revised Unabridged Dictionary · 1913

Fun

Fun (fun) , noun

[Perh. of Celtic origin; compare Ir. & Gael. fonn pleasure.]

Sport; merriment; frolicsome amusement.
Oddity, frolic, and fun. — Goldsmith
Collocations (1)
To make fun of , to hold up to, or turn into, ridicule.

fun (fun) , adjective

Of or pertaining to fun; causing pleasure or amusement; as, a fun thing to do. [colloquial or jocular; informal]