Official back to cover essential point, right (9)
I believe the answer is:
registrar
'official' is the definition.
(registrar is a kind of official)
'back to cover essential point right' is the wordplay.
'back' becomes 'rear' (something's rear is its back).
'to cover' indicates putting letters inside.
'essential point' becomes 'gist' (I've seen this in another clue).
'right' becomes 'r' (common abbreviation).
'gist'+'r'='gistr'
'rear' going around 'gistr' is 'REGISTRAR'.
(Other definitions for registrar that I've seen before include "Wedding recorder" , "Mid-ranking doctor" , "Administrator responsible for records" , "University administrator -- hospital doctor" , "Official record-keeper" .)