Held by mate, a sensible bait (5)
I believe the answer is:
tease
'bait' is the definition.
(I know that bait can be written as tease)
'held by mate a sensible' is the wordplay.
'held by' indicates a hidden word.
'TEASE' is hidden in the letters of 'mate a sensible'.
(Other definitions for tease that I've seen before include "Cod" , "Rib, annoy" , "Rib, wind up" , "Gently make fun of (someone)" , "Playfully provoke" .)