Its players pretend to have fun (8)
I believe the answer is:
charades
'fun' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe they are linked in a way I don't understand?
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for charades that I've seen before include "Party guessing game" , "Game in which answers are acted out" , "Games like this" , "Guessing game where words are acted out" , "Miming parlour game" .)