Flat marshy land (3)
I believe the answer is:
fen
(Other definitions for fen that I've seen before include "Low marshy area" , "Slough" , "Low-lying tract of marshy land in England" , "Low marsh" , "Low-lying wet land with grassy vegetation" .)
I believe the answer is:
fen
(Other definitions for fen that I've seen before include "Low marshy area" , "Slough" , "Low-lying tract of marshy land in England" , "Low marsh" , "Low-lying wet land with grassy vegetation" .)