Woman adds moral centre to one down (7)
I believe the answer is:
isadora
'woman' is the definition.
'moral centre to one down' is the wordplay.
'centre' indicates the central letters.
'to' means one lot of letters go next to another (I've seen this in other clues).
'one' becomes 'i' (roman numeral).
'down' becomes 'sad' (I've seen this before).
The central letters of 'moral' are 'ora'.
'i'+'sad'='isad'
'ora' after 'isad' is 'ISADORA'.
'adds' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
(Other definitions for isadora that I've seen before include "-- Duncan, American dancer" , "woman's name" , "girl" , "- Duncan, twentieth century US dancer" , "Famous dancer" .)