Masticate (3)
'masticate' is the definition.
(I know that masticate can be written as chew)
This is all the clue.
(Other definitions for chew that I've seen before include "Masticate, grind between teeth" , "work with canines" , "bit of tobacco" , "Process food" , "Try to eat" .)
(Other definitions for eat that I've seen before include "Ingest" , "Break bread" , "Worry" , "Bit, chew and swallow" , "Devour" .)