Pair eating jerk roll rejected starter (9)
I believe the answer is:
initiator
'starter' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe there's a link between them I don't understand?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for initiator that I've seen before include "originator" , "Substance starting a chain reaction" , "beginner" , "One starts" , "One starting (a process)" .)