Silliness curtailed by outstanding fans (9)
I believe the answer is:
following
'silliness curtailed by outstanding fans' is the definition.
I can't judge whether this defines the answer.
'silliness curtailed by outstanding' is the wordplay.
'silliness' becomes 'folly' (I've seen this before).
'curtailed' means to remove the last letter.
'by' is a charade indicator (letters next to each other).
'outstanding' becomes 'owing' (an outstanding bill is still owing).
'folly' with its final letter removed is 'foll'.
'foll'+'owing'='FOLLOWING'
Can you help me to learn more?
(Other definitions for following that I've seen before include "Understanding" , "Coming after" , "about to be mentioned" , "Body of supporters" , "fans?" .)