Paunch (5)
'paunch' is the definition.
(synonyms)
This is all the clue.
(Other definitions for belly that I've seen before include "Tummy" , "Stomach" , "Abdomen" , "Paunch" , "Corporation" .)
(Other definitions for beer belly that I've seen before include "Spare tyre from drinking ale" , "Protruding stomach due to excessive drinking" , "Spare tyre due to consumption of alcohol" , "Drinker's paunch" , "Protuberant stomach" .)
'paunch' is the definition.
(thesaurus)
This is the entire clue.