Stop running race that's annoying (9)
I believe the answer is:
damnation
'annoying' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'stop running race' is the wordplay.
'stop' becomes 'dam' (I've seen this in other clues).
'running race' becomes 'nation' (both can mean a national or ethnic group. I am not sure about the 'running' bit.).
'dam'+'nation'='DAMNATION'
'that's' acts as a link.
Can you help me to learn more?
(Other definitions for damnation that I've seen before include "angry exclamation?" , "Cursing" , "Denouncing" , "Eternal punishment" , "Mild oath" .)