Beg aloud for something to eat (4)
I believe the answer is:
prey
'something to eat' is the definition.
'beg aloud' is the wordplay.
'beg' becomes 'pray' ('pray' can be a synonym of 'beg').
'aloud' shows a homophone (sound like).
'pray' sounds like 'PREY'.
'for' acts as a link.
(Other definitions for prey that I've seen before include "Animal sought as food" , "Animal hunted or caught for food" , "Quarry, target" , "Animal hunted and killed for food" , "Hunted creature" .)