Diplomatic visit seen to be in error (9)
I believe the answer is:
sensitive
'diplomatic' is the definition.
(thesaurus)
'visit seen to be in error' is the wordplay.
'to be in error' indicates an anagram.
'visit'+'seen'='visitseen'
'visitseen' with letters rearranged gives 'SENSITIVE'.
(Other definitions for sensitive that I've seen before include "Delicate" , "Reacting to external stimuli" , "Tender" , "Responsive to physical stimuli or easily offended" , "Emotional or perceptive" .)