Make your mark as a non-runner? (7)
I believe the answer is:
scratch
'make' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for scratch that I've seen before include "Decide not to play" , "withdraw from tournament" , "Score with a sharp object" , "Withdraw - abrasion" , "Slight cut" .)