Norse deity making duck noise (4)
I believe the answer is:
odin
'norse deity' is the definition.
(Odin is an example)
'duck noise' is the wordplay.
'duck' becomes 'o'.
'noise' becomes 'din' (din is a kind of noise).
'o'+'din'='ODIN'
'making' is the link.
(Other definitions for odin that I've seen before include "God - I nod (anag)" , "The supreme Norse god and creator" , "an all-powerful one" , "King of Norse gods" , "Old Scandinavian" .)