Surface damage caused by bad rust? (4)
I believe the answer is:
ruts
'surface damage caused' is the definition.
I can't tell whether this definition defines the answer.
'bad rust?' is the wordplay.
'bad' is an anagram indicator.
'rust' anagrammed gives 'RUTS'.
'by' acts as a link.
Can you help me to learn more?
(Other definitions for ruts that I've seen before include "Ditches" , "Deep tracks in paths" , "Deep furrows" , "Furrows not to get stuck in" , "gets ready for new partner" .)