Around entrance, holding sparkly white dress down (9)
I believe the answer is:
castigate
'dress down' is the definition.
(castigating is a kind of dressing down)
'around entrance holding sparkly white' is the wordplay.
'around' becomes 'c' (abbreviation for 'circa').
'entrance' becomes 'gate' (type of entrance).
'holding' means one lot of letters goes inside another.
'sparkly white' becomes 'asti' (I am not sure about this - if you are sure you should believe this answer much more).
'c'+'gate'='cgate'
'cgate' going around 'asti' is 'CASTIGATE'.
Can you help me to learn more?
(Other definitions for castigate that I've seen before include "Take a piece out of" , "Chastise - tacit sage (anag)" , "Slap down" , "Rebuke severely" , "Severely reprimand" .)