Brushed-up hair, yours and my charm (7)
I believe the answer is:
enamour
'charm' is the definition.
('enamour' can be a synonym of 'charm')
'brushed-up hair yours and my' is the wordplay.
'brushed up' says the letters should be written backwards (in a down clue, letters go up).
'hair' becomes 'mane' (I have seen 'Long hair ' mean 'mane' so perhaps 'hair' could also mean 'mane').
'yours and my' becomes 'our' (I've seen this before).
'mane' in reverse letter order is 'enam'.
'enam'+'our'='ENAMOUR'
(Other definitions for enamour that I've seen before include "Enchant" , "sweep one off one's feet" , "Delight" , "Fill with love" , "Our name (anag)" .)