Gives up fun (5)
I believe the answer is:
kicks
I believe this is a double definition.
'gives up' is the first definition.
(kicking is a kind of giving up)
'fun' is the second definition.
(what do you do for kicks)
(Other definitions for kicks that I've seen before include "What 8 [SHEARER] does" , "Gives up" , "Spurs?" , "jerks" , "Sudden pleasurable excitements" .)