Old Italian-style manor (5)
I believe the answer is:
roman
'old italian' is the definition.
(I've seen this before)
'style manor' is the wordplay.
'style' indicates an anagram (style can mean to shape or design).
'manor' is an anagram of 'ROMAN'.
(Other definitions for roman that I've seen before include "Caesar, for instance" , "A novel" , "Classical" , "eg Brutus" , "Dominant political power of first centuries AD" .)