Fine atmosphere in travelling entertainment (4)
I believe the answer is:
fair
'travelling entertainment' is the definition.
(travelling fair)
'fine atmosphere' is the wordplay.
'fine' becomes 'f' (abbreviation).
'atmosphere' becomes 'air' (synonyms).
'f'+'air'='FAIR'
'in' is the link.
(Other definitions for fair that I've seen before include "Just; sunny" , "Pretty; impartial" , "Blonde or equitable" , "Just; passable" , "Pretty good" .)