Belt round for a bit of fun, somewhere warm (7)
I believe the answer is:
suntrap
'bit of fun somewhere warm' is the definition.
I can't judge whether this definition defines the answer.
'belt round for a' is the wordplay.
'belt' becomes 's trap' (I've seen this before).
'round' is an insertion indicator.
'for a' becomes 'un' (I can't justify this - if you can you should believe this answer much more).
'strap' enclosing 'un' is 'SUNTRAP'.
Can you help me to learn more?
(Other definitions for suntrap that I've seen before include "conservatory" , "hot spot" , "Some people's ideal garden" , "where it could get hot" , "Warm sheltered spot" .)