Hunger reminder (4)
I believe the answer is:
pang
'hunger reminder' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for pang that I've seen before include "Sharp twinge of pain" , "Sharp pain, of hunger or emotion perhaps" , "Sharp emotional pain" , "Short violent pain" , "Sudden feeling of hunger or pain" .)