One stands between a city and its state of unprofessionalism (6)
I believe the answer is:
laical
'one' is the definition.
Although both the answer and definition are adjectives, I cannot see how they can define each other.
'stands between a city and its state of unprofessionalism' is the wordplay.
I cannot quite see how this works, but
'a' is within the answer.
'state' could be 'cal' (short for California) and 'cal' is found within the answer.
The remaining letters 'li' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for laical that I've seen before include "Non-professional" , "Secular" .)