Preempted, perhaps (3,2)
I believe the answer is:
not on
'preempted perhaps' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for not on that I've seen before include "Improper - impossible" , "It's unfeasible" , "Unacceptable (colloq.)" , "Modern phrase for unacceptable" , "Colloquially, cannot be tolerated or accepted" .)