Character in this or that (4)
I believe the answer is:
sort
'character' is the definition.
(I've seen this in another clue)
'in this or that' is the wordplay.
'in' indicates the answer is hidden within the clue.
'SORT' can be found hidden inside 'this or that'.
(Other definitions for sort that I've seen before include "class" , "Type - arrange in groups" , "Group" , "Shuffle into desired sequence" , "Classify; kind" .)