Bumper flaw (4)
I believe the answer is:
dent
'bumper flaw' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for dent that I've seen before include "'Dinge, depression (4)'" , "Injury to pride" , "Small hollow" , "Tend to small indentation" , "Slight damage" .)