Furry aquatic mammal (5)
I believe the answer is:
otter
'furry aquatic mammal' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for otter that I've seen before include "Semi-aquatic mammal" , "Freshwater brown carnivore" , "Water mammal" , "Mine is made safe by this" , "Fish-eating mammal" .)