Shut up and eat! (4)
I believe the answer is:
bolt
This clue is a double definition.
'shut up' is the first definition.
(thesaurus)
'eat' is the second definition.
(bolting is a kind of eating)
'and' is the link.
(Other definitions for bolt that I've seen before include "writer" , "wolf" , "Lock - run away - gobble - lightning flash - cloth roll" , "Fasten - flee" , "one may be shot" .)