Now, expert is smart (11)
I believe the answer is:
presentable
'is smart' is the definition.
'now expert' is the wordplay.
'now' becomes 'present' (I've seen this before).
'expert' becomes 'able' (I've seen this in other clues).
'present'+'able'='PRESENTABLE'
(Other definitions for presentable that I've seen before include "Neat" , "Decent" , "Fit to be seen in public" , "Fit for public scrutiny" .)