Substitute for modesty? (7)
I believe the answer is:
reserve
This clue is a double definition.
'substitute' is the first definition.
('reserve' can be a synonym of 'substitute')
'modesty?' is the second definition.
('reserve' can be a synonym of 'modesty')
'for' is the link.
(Other definitions for reserve that I've seen before include "Lack of openness" , "some distance" , "Set aside - shyness" , "Keep for someone - spare bod" , "Order" .)