Swell coming from vessel circling lake (5)
I believe the answer is:
bloat
'swell' is the definition.
(bloating is a kind of swelling)
'vessel circling lake' is the wordplay.
'vessel' becomes 'boat' (boat is a kind of vessel**).
'circling' means one lot of letters goes inside another (circling can mean going around or containing).
'lake' becomes 'l'.
'boat' going around 'l' is 'BLOAT'.
'coming from' is the link.
(Other definitions for bloat that I've seen before include "Fill up with gas" , "Make swollen" , "Cause to swell" , "Puff out" , "Swell with fluid or gas" .)