Perfect control embracing female sweetheart (6)
I believe the answer is:
refine
'perfect' is the definition.
(I've seen this in another clue)
'control embracing female sweetheart' is the wordplay.
'control' becomes 'rein' (synonyms).
'embracing' means one lot of letters goes inside another.
'female' becomes 'f' (common abbreviation).
'sweetheart' becomes 'e' (the heart/centre of 'sweet').
'rein' enclosing 'f' is 'refin'.
'refin'+'e'='REFINE'
(Other definitions for refine that I've seen before include "Make purer" , "Remove impurities or make cultured" , "Purify or improve" , "Get rid of impurities" , "Remove impurities as from oil" .)