Reasonable form of entertainment (4)
I believe the answer is:
fair
This clue is a double definition.
'reasonable' is the first definition.
(I know that reasonable can be written as fair)
'form of entertainment' is the second definition.
(I know that fair is a type of show)
(Other definitions for fair that I've seen before include "Just; sunny" , "Blonde; beautiful" , "Pretty good" , "Reasonable target?" , "square" .)