Lack of harmony in road behind dance club (7)
I believe the answer is:
discord
'lack of harmony' is the definition.
(I've seen this in another clue)
'road behind dance club' is the wordplay.
'road' becomes 'rd' (abbreviation).
'behind' is a charade indicator (letters next to each other).
'dance club' becomes 'disco' (I've seen this in another clue).
'rd' put after 'disco' is 'DISCORD'.
'in' is the link.
(Other definitions for discord that I've seen before include "Dissension" , "contention" , "Disagreement" , "Friction" , "Opposition" .)