Cut needed in extra injury
I believe the answer is:
black eye
'injury' is the definition.
(black eye is a kind of injury)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for black eye that I've seen before include "Kind of bruise - kind of bean" , "Outcome of strike" , "Facial bruising" , "Result of blow to optic" , "Shiner" .)