Seaborne ice-mass (4)
I believe the answer is:
berg
(Other definitions for berg that I've seen before include "One who scored" , "Mass of ice floating at sea" , "Lump of ice" , "trouble at sea" , "Mountain (in German, South African)" .)
I believe the answer is:
berg
(Other definitions for berg that I've seen before include "One who scored" , "Mass of ice floating at sea" , "Lump of ice" , "trouble at sea" , "Mountain (in German, South African)" .)