An aquatic bird seen on the Nile (5)
I believe the answer is:
aswan
'the nile' is the definition.
Both the definition and answer are singular nouns.
Perhaps you can see an association between them that I don't see?
'an aquatic bird' is the wordplay.
'an' becomes 'a'.
'aquatic bird' becomes 'swan' (swan is a kind of aquatic bird).
'a'+'swan'='ASWAN'
'seen on' is the link.
Can you help me to learn more?
(Other definitions for aswan that I've seen before include "Nile High Dam" , "Site of dam in Egypt" , "Site of dam on the Nile" , "Egyptian city and dam" , "Egyptian town and dam" .)