Play for fun (6)
I believe the answer is:
comedy
This clue is a double definition.
'play' is the first definition.
(comedy is a kind of play)
'fun' is the second definition.
(comedy is a kind of fun)
'for' acts as a link.
(Other definitions for comedy that I've seen before include "provides amusement" , "film like Doctor in the House" , "Play with happy ending" , "Funny and/or happy play" , "Light and humorous drama" .)