Polish girl's complaint (7)
I believe the answer is:
rubella
'complaint' is the definition.
(rubella is a kind of disease)
'polish girl's' is the wordplay.
'polish' becomes 'rub' (polish meaning rub to make shiny).
'girl' becomes 'ella'.
'rub'+'ella'='RUBELLA'
(Other definitions for rubella that I've seen before include "contagious disease" , "infection" , "complaint" , "German measles" .)