Correct, somewhat vindicated I thought (4)
I believe the answer is:
edit
'correct' is the definition.
(edit can mean to correct or emend)
'somewhat vindicated i thought' is the wordplay.
'somewhat' indicates a hidden word.
'EDIT' is hidden within 'vindicated i thought'.
(Other definitions for edit that I've seen before include "Make alterations (in text)" , "This is an act of cleaning" , "Check text for publication" , "Censor" , "Amend and correct" .)