Seal hunter directly opposite harbour (5,4)
I believe the answer is:
polar bear
'seal hunter' is the definition.
The answer and definition can be both animals as well as being singular nouns.
Maybe there's an association between them I don't understand?
'directly opposite harbour' is the wordplay.
'directly opposite' becomes 'polar' (I've seen this before).
'harbour' becomes 'bear' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'polar'+'bear'='POLAR BEAR'
Can you help me to learn more?
(Other definitions for polar bear that I've seen before include "big brute" , "Arctic mammal" , "Arctic creature" , "Arctic pack ice resident" , "Arctic carnivore" .)