Use garden rocks and overalls (9)
I believe the answer is:
dungarees
'overalls' is the definition.
(I have seen 'Durable overalls ' mean 'dungarees' so perhaps 'overalls' could also mean 'dungarees')
'use garden rocks' is the wordplay.
'rocks' is an anagram indicator.
'use'+'garden'='usegarden'
'usegarden' is an anagram of 'DUNGAREES'.
'and' acts as a link.
(Other definitions for dungarees that I've seen before include "Work overalls" , "Durable overalls" , "overalls required" , "garment" , "Overall" .)