Distend (5)
'distend' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for swell that I've seen before include "Puff up" , "Movement of the surface of the sea" , "Become larger or rounder" , "Balloon - movement of the sea's surface" , "part of organ" .)
'distend' is the definition.
(bloating is a kind of distending)
This is all the clue.
(Other definitions for bloat that I've seen before include "Fill up with gas" , "Puff out" , "Cause to swell" , "Make swollen" , "Thus treat some fish" .)