Yours truly's taking in good female American who needs education (9)
I believe the answer is:
ignoramus
'who needs education' is the definition.
'yours truly's taking in good female american' is the wordplay.
'yours truly's' becomes 'im' (I'm).
'taking in' is an insertion indicator.
'good' becomes 'g' (abbreviation).
'female' becomes 'nora' (woman's name**).
'american' becomes 'us'.
'g'+'nora'='gnora'
'im' placed around 'gnora' is 'ignoram'.
'ignoram'+'us'='IGNORAMUS'
(Other definitions for ignoramus that I've seen before include "One could be blissful it's said" , "One who knows nothing" , "Stupid person" , "Idiot" , "Fool" .)