Wet, waterlogged (6)
I believe the answer is:
I believe this clue is a double definition.
'wet' is the first definition.
(similar in meaning)
'waterlogged' is the second definition.
(I know that waterlogged can be written as marshy)
(Other definitions for marshy that I've seen before include "Soggy" , "treacherous underfoot" , "Waterlogged ground" , "Long narrow mark" , "like Slough" .)