Groupie (3)
I believe the answer is:
'groupie' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for fan that I've seen before include "Cooling device for enthusiastic supporter" , "Devoted admirer or air cooler" , "Manually wielded cooling device" , "Lady Windermere's - -" , "Aficionado" .)