Introduce gradually in new list (6)
I believe the answer is:
instil
'introduce gradually' is the definition.
(I've seen this before)
'in new list' is the wordplay.
'new' indicates an anagram.
'list' is an anagram of 'stil'.
'in'+'stil'='INSTIL'
(Other definitions for instil that I've seen before include "Drill" , "It's nil (anag.)" , "Gradually establish (in someone's mind)" , "Put in drop by drop" , "Put gradually into mind" .)