Bear ought to sound hesitant (8)
I believe the answer is:
shoulder
'bear' is the definition.
(both can mean to carry or take responsibility for)
'ought to sound hesitant' is the wordplay.
'ought to' becomes 'should' ('you ought to' means 'you should').
'sound hesitant' becomes 'er' (sound made when hesitating).
'should'+'er'='SHOULDER'
(Other definitions for shoulder that I've seen before include "Meat joint" , "Take burden onto this joint" , "Old usher, oddly, is part of the body" , "Joint - ours held (anag)" , "Top of the arm" .)