Regret being impolite, putting daughter out (3)
I believe the answer is:
rue
'regret' is the definition.
(to rue something is to regret it)
I don't understand the rest of the clue.
(Other definitions for rue that I've seen before include "French way" , "way Parisians go about" , "Regret in a French street" , "Regret, be sorry for" , "Repentant sort of shrub?" .)