Skip about in Polish coat (9)
I believe the answer is:
sheepskin
'coat' is the definition.
(sheepskin coat is a kind of coat)
'skip about in polish' is the wordplay.
'about' indicates anagramming the letters.
'in' means one lot of letters goes inside another.
'polish' becomes 'sheen' (both can mean a shiny surface).
'skip' anagrammed gives 'pski'.
'pski' put inside 'sheen' is 'SHEEPSKIN'.
(Other definitions for sheepskin that I've seen before include "Woolly pelt" , "coat" , "Body covering of an ovine mammal" , "Fleece garment" , "leather" .)