Thoughtful sort (4)
I believe the answer is:
kind
This clue is a double definition.
'thoughtful' is the first definition.
('kind' can be a synonym of 'thoughtful')
'sort' is the second definition.
('kind' can be a synonym of 'sort')
(Other definitions for kind that I've seen before include "Friendly - type" , "Gracious" , "Class, type" , "Sort; gentle" , "Taking a plunge" .)