Manifest past transgression on initiation (5)
I believe the answer is:
overt
'manifest' is the definition.
(I've seen this in another clue)
'past transgression on initiation' is the wordplay.
'past' becomes 'over' (I've seen this before).
'transgression on initiation' becomes 't' (I can't explain this - if you can you should give a lot more credence to this answer).
'over'+'t'='OVERT'
Can you help me to learn more?
(Other definitions for overt that I've seen before include "Done in an obvious way" , "Open and observable" , "Open,up front" , "Obvious, patent" , "Open, up front" .)