Venue taking a long time to make comeback (5)
I believe the answer is:
arena
'venue' is the definition.
(I know that venue can be written as arena)
'a long time to make comeback' is the wordplay.
'a' becomes 'an'.
'long time' becomes 'era' (a long period of time).
'to make comeback' says the letters should be written backwards (I've seen 'making comeback' mean this).
'an'+'era'='anera'
'anera' in reverse letter order is 'ARENA'.
'taking' acts as a link.
(Other definitions for arena that I've seen before include "Playing area" , "Area of activity, boxing perhaps" , "Playing field or boxing ring" , "battlefieId" , "where there's competition" .)