Carelessness evident, having cut right cheek (9)
I believe the answer is:
impudence
'cheek' is the definition.
(I know that cheek can be written as impudence)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for impudence that I've seen before include "Cheek" , "Sauce" , "assurance" , "Audacity" , "Boldness and insolence" .)