Passed with top grade, after clear knowledge (9)
I believe the answer is:
overtaken
'passed' is the definition.
('overtake' can be a synonym of 'pass')
'with top grade after clear knowledge' is the wordplay.
'with' indicates putting letters inside.
'top grade' becomes 'A' (top academic grade).
'after clear' becomes 'overt' (both can mean apparent or obvious. I am not sure about the 'after' bit.).
'knowledge' becomes 'ken' (ken is a kind of knowledge).
'overt'+'ken'='overtken'
'a' put within 'overtken' is 'OVERTAKEN'.
(Other definitions for overtaken that I've seen before include "Passed on road" , "left behind" .)