Fat fee mine when dressed as woman (10)
I believe the answer is:
effeminate
'as woman' is the definition.
'fat fee mine when dressed' is the wordplay.
'when dressed' indicates anagramming the letters ('dressed' can mean 'prepared').
'fat'+'fee'+'mine'='fatfeemine'
'fatfeemine' with letters rearranged gives 'EFFEMINATE'.
(Other definitions for effeminate that I've seen before include "Womanly" , "Acting like a woman" , "camp" , "(Of a man) having female characteristics" , "sissy?" .)