Ancient city not quite superior to all others (6)

I believe the answer is:

thebes

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'ancient city' is the definition.
(ancient Greek city)

I cannot understand how the rest of the clue works.

(Other definitions for thebes that I've seen before include "Old Egyptian city" , "Greek city founded by Cadmus" , "Classical city" , "Ancient Egyptian city sited at modern-day Luxor" , "Old city of Greece or Egypt" .)

I've seen this clue in The Times.

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