The girl with a red top or fleece (5)
I believe the answer is:
shear
'fleece' is the definition.
('shear' can be a synonym of 'fleece')
'the girl with a red top' is the wordplay.
'the girl' becomes 'shea' (**).
'with' is a charade indicator (letters next to each other).
'top' indicates taking the first letters.
The first letter of 'red' is 'r'.
'shea'+'r'='SHEAR'
'or' acts as a link.
(Other definitions for shear that I've seen before include "Cut sheep's woll with large scissors" , "Cutter" , "Cut the wool of 14 across" , "Clip a sheep" , "Cut wool off (a sheep)" .)