A girl after a bit of butter for her kneecap (7)
I believe the answer is:
patella
'kneecap' is the definition.
(I know that kneecap can be written as patella)
'a girl after a bit of butter' is the wordplay.
'a girl' becomes 'Ella' (girl's name).
'after' says to put letters next to each other.
'a bit of butter' becomes 'pat' (I've seen this in another clue).
'ella' after 'pat' is 'PATELLA'.
'for her' acts as a 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 patella that I've seen before include "Joint cover" , "Kneecap (anatomy)" , "positioned on each knee" , "bit of body usually under trousers!" , "showing a bit of leg" .)