Combination of city and sea, not a representation (9)
I believe the answer is:
syndicate
'representation' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'combination of city and sea not a' is the wordplay.
'combination of' is an anagram indicator (I've seen this in other clues).
'not' suggests deleting specific letters.
'city'+'and'+'sea'='cityandsea'
'cityandsea' with 'a' taken out is 'cityndsea'.
'cityndsea' with letters rearranged gives 'SYNDICATE'.
Can you help me to learn more?
(Other definitions for syndicate that I've seen before include "Nay, edicts changed for the business association" , "Group of promoters with a common interest" , "Team" , "Publish across several papers" , "We might enter lottery" .)