Savant (4)
I believe the answer is:
sage
'savant' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sage that I've seen before include "cheesemongers associate with Derby" , "Feature of herb garden" , "Velvety-leaved herb" , "Solon, for instance" , "Culinary herb" .)