Roman-style villa (5)
I believe the answer is:
manor
'villa' is the definition.
(thesaurus)
'roman-style' is the wordplay.
'style' indicates anagramming the letters (style can mean to shape or design).
'roman' is an anagram of 'MANOR'.
(Other definitions for manor that I've seen before include "lord's home" , "police area" , "local copper's area" , "Landed estate" , "Mansion of a wealthy person" .)