Sheep wandering in Rome (6)
I believe the answer is:
merino
'sheep' is the definition.
(breed of sheep)
'wandering in rome' is the wordplay.
'wandering' indicates an anagram.
'in'+'rome'='inrome'
'inrome' is an anagram of 'MERINO'.
(Other definitions for merino that I've seen before include "Sheep from Spain with a heavy quality fleece" , "Fine woollen yarn" , "Sheep with fine quality fleece" , "Sheep with fine soft wool" , "Fine soft woolen yarn" .)