Eccentric one wants only female underwear (8)
I believe the answer is:
camisole
'female underwear' is the definition.
'eccentric one wants only' is the wordplay.
'eccentric' becomes 'cam' (an eccentric is a mechanical device such as a cam).
'one' becomes 'i' (Roman numeral).
'wants' is a charade indicator (letters next to each other).
'only' becomes 'sole' ('sole' can be a synonym of 'only').
'cam'+'i'+'sole'='CAMISOLE'
(Other definitions for camisole that I've seen before include "Loose undergarment" , "item of underwear" , "Top" , "Loose underbodice" , "Item of lingerie" .)