Kind heart of dancing girl (5)
I believe the answer is:
class
'kind' is the definition.
(I've seen this before)
'heart of dancing girl' is the wordplay.
'heart of' says to take the centre.
'girl' becomes 'lass' (lass can informally mean a girl).
The central letter of 'dancing' is 'c'.
'c'+'lass'='CLASS'
(Other definitions for class that I've seen before include "26 [ORDER]" , "Where one learns" , "High quality" , "Rank" , "Body of students" .)