Resort on rocks, one in Italy (8)
I believe the answer is:
sorrento
'one in italy' is the definition.
The definition suggests a singular noun which matches the answer.
'resort on rocks' is the wordplay.
'rocks' is an anagram indicator.
'resort'+'on'='resorton'
'resorton' anagrammed gives 'SORRENTO'.
(Other definitions for sorrento that I've seen before include "site south of Naples" , "Resort in Campania" , "Resort on the Bay of Naples" , "Italian town on bay of Naples" , "City on the Gulf of Naples" .)