Pester Republican with emblem of office (6)
I believe the answer is:
badger
'pester' is the definition.
('badger' can be a synonym of 'pester')
'republican with emblem of office' is the wordplay.
'republican' becomes 'r' (abbreviation).
'with' is a charade indicator (letters next to each other).
'emblem of office' becomes 'badge' (I've seen this before).
'r' after 'badge' is 'BADGER'.
(Other definitions for badger that I've seen before include "Burrowing carnivore" , "Black and white animal called Brock" , "One of the weasel family" , "Nocturnal black and white animal" , "Plague - nocturnal animal" .)