Baker leaves breakfast to go hungry (4)
I believe the answer is:
fast
'go hungry' is the definition.
(I've seen this before)
'baker leaves breakfast' is the wordplay.
'leaves' is a deletion indicator.
'breakfast' with 'baker' taken away is 'FAST'.
'to' is the link.
(Other definitions for fast that I've seen before include "Maybe bound to spot" , "Securely fixed" , "Rapid; firm" , "Dissolute" , "Period without food" .)