Sarah's disturbed badger (6)
I believe the answer is:
harass
'badger' is the definition.
(I know this)
'sarah's disturbed' is the wordplay.
'disturbed' indicates anagramming the letters (the order of letters is disturbed).
'sarahs' anagrammed gives 'HARASS'.
(Other definitions for harass that I've seen before include "bug" , "Nag" , "Persistently torment" , "Persistently pester" , "Bother and annoy continuously" .)