Dancing and having a good time on a reduced diet (6)
I believe the answer is:
ballet
'dancing' is the definition.
(I know that ballet is a type of choreography)
'good time on a reduced diet' is the wordplay.
'good time' becomes 'ball' (I've seen this in another clue).
'on' is a charade indicator (letters next to each other).
'a reduced diet' becomes 'et' (I am not sure about this - if you are sure you should believe this answer much more).
'ball'+'et'='BALLET'
'and having a' is the link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for ballet that I've seen before include "Classical dancing style" , "Theatrical dance" , "Dance art form" , "old madrigal" , "kind of skirt" .)